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mariadb/mysql-test/r/join_cache.result
Igor Babaev 7f52af655a Merge.
2010-12-10 23:23:34 -08:00

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DROP TABLE IF EXISTS t1,t2,t3,t4,t5,t6,t7,t8,t9,t10,t11;
DROP DATABASE IF EXISTS world;
set @save_optimizer_switch=@@optimizer_switch;
set @@optimizer_switch='semijoin_with_cache=on';
set @@optimizer_switch='outer_join_with_cache=on';
set names utf8;
CREATE DATABASE world;
use world;
CREATE TABLE Country (
Code char(3) NOT NULL default '',
Name char(52) NOT NULL default '',
SurfaceArea float(10,2) NOT NULL default '0.00',
Population int(11) NOT NULL default '0',
Capital int(11) default NULL
) COLLATE latin1_bin;
CREATE TABLE City (
ID int(11) NOT NULL,
Name char(35) NOT NULL default '',
Country char(3) NOT NULL default '',
Population int(11) NOT NULL default '0'
) COLLATE latin1_bin;
CREATE TABLE CountryLanguage (
Country char(3) NOT NULL default '',
Language char(30) NOT NULL default '',
Percentage float(3,1) NOT NULL default '0.0'
) COLLATE latin1_bin;
SELECT COUNT(*) FROM Country;
COUNT(*)
239
SELECT COUNT(*) FROM City;
COUNT(*)
4079
SELECT COUNT(*) FROM CountryLanguage;
COUNT(*)
984
show variables like 'join_buffer_size';
Variable_name Value
join_buffer_size 131072
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 1
EXPLAIN
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country ALL NULL NULL NULL NULL 239 Using where
1 SIMPLE City ALL NULL NULL NULL NULL 4079 Using where; Using join buffer (flat, BNL join)
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
EXPLAIN
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country ALL NULL NULL NULL NULL 239 Using where
1 SIMPLE CountryLanguage ALL NULL NULL NULL NULL 984 Using where; Using join buffer (flat, BNL join)
1 SIMPLE City ALL NULL NULL NULL NULL 4079 Using where; Using join buffer (flat, BNL join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
Name Name Language
Leiden Netherlands Dutch
La Matanza Argentina Spanish
Lomas de Zamora Argentina Spanish
La Plata Argentina Spanish
Lanús Argentina Spanish
Las Heras Argentina Spanish
La Rioja Argentina Spanish
Liège Belgium Dutch
La Paz Bolivia Spanish
Londrina Brazil Portuguese
Limeira Brazil Portuguese
Lages Brazil Portuguese
Luziânia Brazil Portuguese
Lauro de Freitas Brazil Portuguese
Linhares Brazil Portuguese
London United Kingdom English
Liverpool United Kingdom English
Leeds United Kingdom English
Leicester United Kingdom English
Luton United Kingdom English
Los Angeles Chile Spanish
La Serena Chile Spanish
La Romana Dominican Republic Spanish
Loja Ecuador Spanish
Luxor Egypt Arabic
Las Palmas de Gran Canaria Spain Spanish
L´Hospitalet de Llobregat Spain Spanish
Leganés Spain Spanish
León Spain Spanish
Logroño Spain Spanish
Lleida (Lérida) Spain Spanish
Le-Cap-Haïtien Haiti Haiti Creole
La Ceiba Honduras Spanish
Livorno Italy Italian
Latina Italy Italian
Lecce Italy Italian
La Spezia Italy Italian
Linz Austria German
London Canada English
Laval Canada English
Longueuil Canada English
Lanzhou China Chinese
Luoyang China Chinese
Liuzhou China Chinese
Liaoyang China Chinese
Liupanshui China Chinese
Liaoyuan China Chinese
Lianyungang China Chinese
Leshan China Chinese
Linyi China Chinese
Luzhou China Chinese
Laiwu China Chinese
Liaocheng China Chinese
Laizhou China Chinese
Linfen China Chinese
Liangcheng China Chinese
Longkou China Chinese
Langfang China Chinese
Liu´an China Chinese
Longjing China Chinese
Lengshuijiang China Chinese
Laiyang China Chinese
Longyan China Chinese
Linhe China Chinese
Leiyang China Chinese
Loudi China Chinese
Luohe China Chinese
Linqing China Chinese
Laohekou China Chinese
Linchuan China Chinese
Lhasa China Chinese
Lianyuan China Chinese
Liyang China Chinese
Liling China Chinese
Linhai China Chinese
Larisa Greece Greek
La Habana Cuba Spanish
Lilongwe Malawi Chichewa
León Mexico Spanish
La Paz Mexico Spanish
La Paz Mexico Spanish
Lázaro Cárdenas Mexico Spanish
Lagos de Moreno Mexico Spanish
Lerdo Mexico Spanish
Los Cabos Mexico Spanish
Lerma Mexico Spanish
Las Margaritas Mexico Spanish
Lashio (Lasho) Myanmar Burmese
Lalitapur Nepal Nepali
León Nicaragua Spanish
Lambaré Paraguay Spanish
Lima Peru Spanish
Lisboa Portugal Portuguese
Lódz Poland Polish
Lublin Poland Polish
Legnica Poland Polish
Lyon France French
Le Havre France French
Lille France French
Le Mans France French
Limoges France French
Linköping Sweden Swedish
Lund Sweden Swedish
Leipzig Germany German
Lübeck Germany German
Ludwigshafen am Rhein Germany German
Leverkusen Germany German
Lünen Germany German
Lahti Finland Finnish
Lausanne Switzerland German
Latakia Syria Arabic
Luchou Taiwan Min
Lungtan Taiwan Min
Liberec Czech Republic Czech
Lviv Ukraine Ukrainian
Lugansk Ukraine Ukrainian
Lutsk Ukraine Ukrainian
Lysyt?ansk Ukraine Ukrainian
Lower Hutt New Zealand English
Lida Belarus Belorussian
Los Teques Venezuela Spanish
Lipetsk Russian Federation Russian
Ljubertsy Russian Federation Russian
Leninsk-Kuznetski Russian Federation Russian
Long Xuyen Vietnam Vietnamese
Los Angeles United States English
Las Vegas United States English
Long Beach United States English
Lexington-Fayette United States English
Louisville United States English
Lincoln United States English
Lubbock United States English
Little Rock United States English
Laredo United States English
Lakewood United States English
Lansing United States English
Lancaster United States English
Lafayette United States English
Lowell United States English
Livonia United States English
set join_cache_level=2;
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 2
EXPLAIN
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country ALL NULL NULL NULL NULL 239 Using where
1 SIMPLE City ALL NULL NULL NULL NULL 4079 Using where; Using join buffer (flat, BNL join)
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
EXPLAIN
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country ALL NULL NULL NULL NULL 239 Using where
1 SIMPLE CountryLanguage ALL NULL NULL NULL NULL 984 Using where; Using join buffer (flat, BNL join)
1 SIMPLE City ALL NULL NULL NULL NULL 4079 Using where; Using join buffer (incremental, BNL join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
Name Name Language
Leiden Netherlands Dutch
La Matanza Argentina Spanish
Lomas de Zamora Argentina Spanish
La Plata Argentina Spanish
Lanús Argentina Spanish
Las Heras Argentina Spanish
La Rioja Argentina Spanish
Liège Belgium Dutch
La Paz Bolivia Spanish
Londrina Brazil Portuguese
Limeira Brazil Portuguese
Lages Brazil Portuguese
Luziânia Brazil Portuguese
Lauro de Freitas Brazil Portuguese
Linhares Brazil Portuguese
London United Kingdom English
Liverpool United Kingdom English
Leeds United Kingdom English
Leicester United Kingdom English
Luton United Kingdom English
Los Angeles Chile Spanish
La Serena Chile Spanish
La Romana Dominican Republic Spanish
Loja Ecuador Spanish
Luxor Egypt Arabic
Las Palmas de Gran Canaria Spain Spanish
L´Hospitalet de Llobregat Spain Spanish
Leganés Spain Spanish
León Spain Spanish
Logroño Spain Spanish
Lleida (Lérida) Spain Spanish
Le-Cap-Haïtien Haiti Haiti Creole
La Ceiba Honduras Spanish
Livorno Italy Italian
Latina Italy Italian
Lecce Italy Italian
La Spezia Italy Italian
Linz Austria German
London Canada English
Laval Canada English
Longueuil Canada English
Lanzhou China Chinese
Luoyang China Chinese
Liuzhou China Chinese
Liaoyang China Chinese
Liupanshui China Chinese
Liaoyuan China Chinese
Lianyungang China Chinese
Leshan China Chinese
Linyi China Chinese
Luzhou China Chinese
Laiwu China Chinese
Liaocheng China Chinese
Laizhou China Chinese
Linfen China Chinese
Liangcheng China Chinese
Longkou China Chinese
Langfang China Chinese
Liu´an China Chinese
Longjing China Chinese
Lengshuijiang China Chinese
Laiyang China Chinese
Longyan China Chinese
Linhe China Chinese
Leiyang China Chinese
Loudi China Chinese
Luohe China Chinese
Linqing China Chinese
Laohekou China Chinese
Linchuan China Chinese
Lhasa China Chinese
Lianyuan China Chinese
Liyang China Chinese
Liling China Chinese
Linhai China Chinese
Larisa Greece Greek
La Habana Cuba Spanish
Lilongwe Malawi Chichewa
León Mexico Spanish
La Paz Mexico Spanish
La Paz Mexico Spanish
Lázaro Cárdenas Mexico Spanish
Lagos de Moreno Mexico Spanish
Lerdo Mexico Spanish
Los Cabos Mexico Spanish
Lerma Mexico Spanish
Las Margaritas Mexico Spanish
Lashio (Lasho) Myanmar Burmese
Lalitapur Nepal Nepali
León Nicaragua Spanish
Lambaré Paraguay Spanish
Lima Peru Spanish
Lisboa Portugal Portuguese
Lódz Poland Polish
Lublin Poland Polish
Legnica Poland Polish
Lyon France French
Le Havre France French
Lille France French
Le Mans France French
Limoges France French
Linköping Sweden Swedish
Lund Sweden Swedish
Leipzig Germany German
Lübeck Germany German
Ludwigshafen am Rhein Germany German
Leverkusen Germany German
Lünen Germany German
Lahti Finland Finnish
Lausanne Switzerland German
Latakia Syria Arabic
Luchou Taiwan Min
Lungtan Taiwan Min
Liberec Czech Republic Czech
Lviv Ukraine Ukrainian
Lugansk Ukraine Ukrainian
Lutsk Ukraine Ukrainian
Lysyt?ansk Ukraine Ukrainian
Lower Hutt New Zealand English
Lida Belarus Belorussian
Los Teques Venezuela Spanish
Lipetsk Russian Federation Russian
Ljubertsy Russian Federation Russian
Leninsk-Kuznetski Russian Federation Russian
Long Xuyen Vietnam Vietnamese
Los Angeles United States English
Las Vegas United States English
Long Beach United States English
Lexington-Fayette United States English
Louisville United States English
Lincoln United States English
Lubbock United States English
Little Rock United States English
Laredo United States English
Lakewood United States English
Lansing United States English
Lancaster United States English
Lafayette United States English
Lowell United States English
Livonia United States English
set join_cache_level=default;
set join_buffer_size=256;
show variables like 'join_buffer_size';
Variable_name Value
join_buffer_size 256
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 1
EXPLAIN
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country ALL NULL NULL NULL NULL 239 Using where
1 SIMPLE City ALL NULL NULL NULL NULL 4079 Using where; Using join buffer (flat, BNL join)
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
EXPLAIN
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country ALL NULL NULL NULL NULL 239 Using where
1 SIMPLE CountryLanguage ALL NULL NULL NULL NULL 984 Using where; Using join buffer (flat, BNL join)
1 SIMPLE City ALL NULL NULL NULL NULL 4079 Using where; Using join buffer (flat, BNL join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
Name Name Language
Leiden Netherlands Dutch
La Matanza Argentina Spanish
Lomas de Zamora Argentina Spanish
La Plata Argentina Spanish
Lanús Argentina Spanish
Las Heras Argentina Spanish
La Rioja Argentina Spanish
Liège Belgium Dutch
La Paz Bolivia Spanish
Londrina Brazil Portuguese
Limeira Brazil Portuguese
Lages Brazil Portuguese
Luziânia Brazil Portuguese
Lauro de Freitas Brazil Portuguese
Linhares Brazil Portuguese
London United Kingdom English
Liverpool United Kingdom English
Leeds United Kingdom English
Leicester United Kingdom English
Luton United Kingdom English
Los Angeles Chile Spanish
La Serena Chile Spanish
La Romana Dominican Republic Spanish
Loja Ecuador Spanish
Luxor Egypt Arabic
Las Palmas de Gran Canaria Spain Spanish
L´Hospitalet de Llobregat Spain Spanish
Leganés Spain Spanish
León Spain Spanish
Logroño Spain Spanish
Lleida (Lérida) Spain Spanish
Le-Cap-Haïtien Haiti Haiti Creole
La Ceiba Honduras Spanish
Livorno Italy Italian
Latina Italy Italian
Lecce Italy Italian
La Spezia Italy Italian
Linz Austria German
London Canada English
Laval Canada English
Longueuil Canada English
Lanzhou China Chinese
Luoyang China Chinese
Liuzhou China Chinese
Liaoyang China Chinese
Liupanshui China Chinese
Liaoyuan China Chinese
Lianyungang China Chinese
Leshan China Chinese
Linyi China Chinese
Luzhou China Chinese
Laiwu China Chinese
Liaocheng China Chinese
Laizhou China Chinese
Linfen China Chinese
Liangcheng China Chinese
Longkou China Chinese
Langfang China Chinese
Liu´an China Chinese
Longjing China Chinese
Lengshuijiang China Chinese
Laiyang China Chinese
Longyan China Chinese
Linhe China Chinese
Leiyang China Chinese
Loudi China Chinese
Luohe China Chinese
Linqing China Chinese
Laohekou China Chinese
Linchuan China Chinese
Lhasa China Chinese
Lianyuan China Chinese
Liyang China Chinese
Liling China Chinese
Linhai China Chinese
Larisa Greece Greek
La Habana Cuba Spanish
Lilongwe Malawi Chichewa
León Mexico Spanish
La Paz Mexico Spanish
La Paz Mexico Spanish
Lázaro Cárdenas Mexico Spanish
Lagos de Moreno Mexico Spanish
Lerdo Mexico Spanish
Los Cabos Mexico Spanish
Lerma Mexico Spanish
Las Margaritas Mexico Spanish
Lashio (Lasho) Myanmar Burmese
Lalitapur Nepal Nepali
León Nicaragua Spanish
Lambaré Paraguay Spanish
Lima Peru Spanish
Lisboa Portugal Portuguese
Lódz Poland Polish
Lublin Poland Polish
Legnica Poland Polish
Lyon France French
Le Havre France French
Lille France French
Le Mans France French
Limoges France French
Linköping Sweden Swedish
Lund Sweden Swedish
Leipzig Germany German
Lübeck Germany German
Ludwigshafen am Rhein Germany German
Leverkusen Germany German
Lünen Germany German
Lahti Finland Finnish
Lausanne Switzerland German
Latakia Syria Arabic
Luchou Taiwan Min
Lungtan Taiwan Min
Liberec Czech Republic Czech
Lviv Ukraine Ukrainian
Lugansk Ukraine Ukrainian
Lutsk Ukraine Ukrainian
Lysyt?ansk Ukraine Ukrainian
Lower Hutt New Zealand English
Lida Belarus Belorussian
Los Teques Venezuela Spanish
Lipetsk Russian Federation Russian
Ljubertsy Russian Federation Russian
Leninsk-Kuznetski Russian Federation Russian
Long Xuyen Vietnam Vietnamese
Los Angeles United States English
Las Vegas United States English
Long Beach United States English
Lexington-Fayette United States English
Louisville United States English
Lincoln United States English
Lubbock United States English
Little Rock United States English
Laredo United States English
Lakewood United States English
Lansing United States English
Lancaster United States English
Lafayette United States English
Lowell United States English
Livonia United States English
set join_cache_level=2;
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 2
EXPLAIN
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country ALL NULL NULL NULL NULL 239 Using where
1 SIMPLE City ALL NULL NULL NULL NULL 4079 Using where; Using join buffer (flat, BNL join)
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
EXPLAIN
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country ALL NULL NULL NULL NULL 239 Using where
1 SIMPLE CountryLanguage ALL NULL NULL NULL NULL 984 Using where; Using join buffer (flat, BNL join)
1 SIMPLE City ALL NULL NULL NULL NULL 4079 Using where; Using join buffer (incremental, BNL join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
Name Name Language
Leiden Netherlands Dutch
La Matanza Argentina Spanish
Lomas de Zamora Argentina Spanish
La Plata Argentina Spanish
Lanús Argentina Spanish
Las Heras Argentina Spanish
La Rioja Argentina Spanish
Liège Belgium Dutch
La Paz Bolivia Spanish
Londrina Brazil Portuguese
Limeira Brazil Portuguese
Lages Brazil Portuguese
Luziânia Brazil Portuguese
Lauro de Freitas Brazil Portuguese
Linhares Brazil Portuguese
London United Kingdom English
Liverpool United Kingdom English
Leeds United Kingdom English
Leicester United Kingdom English
Luton United Kingdom English
Los Angeles Chile Spanish
La Serena Chile Spanish
La Romana Dominican Republic Spanish
Loja Ecuador Spanish
Luxor Egypt Arabic
Las Palmas de Gran Canaria Spain Spanish
L´Hospitalet de Llobregat Spain Spanish
Leganés Spain Spanish
León Spain Spanish
Logroño Spain Spanish
Lleida (Lérida) Spain Spanish
Le-Cap-Haïtien Haiti Haiti Creole
La Ceiba Honduras Spanish
Livorno Italy Italian
Latina Italy Italian
Lecce Italy Italian
La Spezia Italy Italian
Linz Austria German
London Canada English
Laval Canada English
Longueuil Canada English
Lanzhou China Chinese
Luoyang China Chinese
Liuzhou China Chinese
Liaoyang China Chinese
Liupanshui China Chinese
Liaoyuan China Chinese
Lianyungang China Chinese
Leshan China Chinese
Linyi China Chinese
Luzhou China Chinese
Laiwu China Chinese
Liaocheng China Chinese
Laizhou China Chinese
Linfen China Chinese
Liangcheng China Chinese
Longkou China Chinese
Langfang China Chinese
Liu´an China Chinese
Longjing China Chinese
Lengshuijiang China Chinese
Laiyang China Chinese
Longyan China Chinese
Linhe China Chinese
Leiyang China Chinese
Loudi China Chinese
Luohe China Chinese
Linqing China Chinese
Laohekou China Chinese
Linchuan China Chinese
Lhasa China Chinese
Lianyuan China Chinese
Liyang China Chinese
Liling China Chinese
Linhai China Chinese
Larisa Greece Greek
La Habana Cuba Spanish
Lilongwe Malawi Chichewa
León Mexico Spanish
La Paz Mexico Spanish
La Paz Mexico Spanish
Lázaro Cárdenas Mexico Spanish
Lagos de Moreno Mexico Spanish
Lerdo Mexico Spanish
Los Cabos Mexico Spanish
Lerma Mexico Spanish
Las Margaritas Mexico Spanish
Lashio (Lasho) Myanmar Burmese
Lalitapur Nepal Nepali
León Nicaragua Spanish
Lambaré Paraguay Spanish
Lima Peru Spanish
Lisboa Portugal Portuguese
Lódz Poland Polish
Lublin Poland Polish
Legnica Poland Polish
Lyon France French
Le Havre France French
Lille France French
Le Mans France French
Limoges France French
Linköping Sweden Swedish
Lund Sweden Swedish
Leipzig Germany German
Lübeck Germany German
Ludwigshafen am Rhein Germany German
Leverkusen Germany German
Lünen Germany German
Lahti Finland Finnish
Lausanne Switzerland German
Latakia Syria Arabic
Luchou Taiwan Min
Lungtan Taiwan Min
Liberec Czech Republic Czech
Lviv Ukraine Ukrainian
Lugansk Ukraine Ukrainian
Lutsk Ukraine Ukrainian
Lysyt?ansk Ukraine Ukrainian
Lower Hutt New Zealand English
Lida Belarus Belorussian
Los Teques Venezuela Spanish
Lipetsk Russian Federation Russian
Ljubertsy Russian Federation Russian
Leninsk-Kuznetski Russian Federation Russian
Long Xuyen Vietnam Vietnamese
Los Angeles United States English
Las Vegas United States English
Long Beach United States English
Lexington-Fayette United States English
Louisville United States English
Lincoln United States English
Lubbock United States English
Little Rock United States English
Laredo United States English
Lakewood United States English
Lansing United States English
Lancaster United States English
Lafayette United States English
Lowell United States English
Livonia United States English
set join_cache_level=default;
set join_buffer_size=default;
show variables like 'join_buffer_size';
Variable_name Value
join_buffer_size 131072
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 1
DROP DATABASE world;
CREATE DATABASE world;
use world;
CREATE TABLE Country (
Code char(3) NOT NULL default '',
Name char(52) NOT NULL default '',
SurfaceArea float(10,2) NOT NULL default '0.00',
Population int(11) NOT NULL default '0',
Capital int(11) default NULL,
PRIMARY KEY (Code),
UNIQUE INDEX (Name)
) COLLATE latin1_bin;
CREATE TABLE City (
ID int(11) NOT NULL auto_increment,
Name char(35) NOT NULL default '',
Country char(3) NOT NULL default '',
Population int(11) NOT NULL default '0',
PRIMARY KEY (ID),
INDEX (Population),
INDEX (Country)
) COLLATE latin1_bin;
CREATE TABLE CountryLanguage (
Country char(3) NOT NULL default '',
Language char(30) NOT NULL default '',
Percentage float(3,1) NOT NULL default '0.0',
PRIMARY KEY (Country, Language),
INDEX (Percentage)
) COLLATE latin1_bin;
show variables like 'join_buffer_size';
Variable_name Value
join_buffer_size 131072
set join_cache_level=3;
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 3
EXPLAIN
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 SIMPLE City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BNLH join)
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
EXPLAIN
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE CountryLanguage ALL PRIMARY,Percentage NULL NULL NULL 984 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.CountryLanguage.Country 1 Using where; Using join buffer (flat, BNLH join)
1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition; Using where
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
Name Name Language
Leiden Netherlands Dutch
La Matanza Argentina Spanish
Lomas de Zamora Argentina Spanish
La Plata Argentina Spanish
Lanús Argentina Spanish
Las Heras Argentina Spanish
La Rioja Argentina Spanish
Liège Belgium Dutch
La Paz Bolivia Spanish
Londrina Brazil Portuguese
Limeira Brazil Portuguese
Lages Brazil Portuguese
Luziânia Brazil Portuguese
Lauro de Freitas Brazil Portuguese
Linhares Brazil Portuguese
London United Kingdom English
Liverpool United Kingdom English
Leeds United Kingdom English
Leicester United Kingdom English
Luton United Kingdom English
Los Angeles Chile Spanish
La Serena Chile Spanish
La Romana Dominican Republic Spanish
Loja Ecuador Spanish
Luxor Egypt Arabic
Las Palmas de Gran Canaria Spain Spanish
L´Hospitalet de Llobregat Spain Spanish
Leganés Spain Spanish
León Spain Spanish
Logroño Spain Spanish
Lleida (Lérida) Spain Spanish
Le-Cap-Haïtien Haiti Haiti Creole
La Ceiba Honduras Spanish
Livorno Italy Italian
Latina Italy Italian
Lecce Italy Italian
La Spezia Italy Italian
Linz Austria German
London Canada English
Laval Canada English
Longueuil Canada English
Lanzhou China Chinese
Luoyang China Chinese
Liuzhou China Chinese
Liaoyang China Chinese
Liupanshui China Chinese
Liaoyuan China Chinese
Lianyungang China Chinese
Leshan China Chinese
Linyi China Chinese
Luzhou China Chinese
Laiwu China Chinese
Liaocheng China Chinese
Laizhou China Chinese
Linfen China Chinese
Liangcheng China Chinese
Longkou China Chinese
Langfang China Chinese
Liu´an China Chinese
Longjing China Chinese
Lengshuijiang China Chinese
Laiyang China Chinese
Longyan China Chinese
Linhe China Chinese
Leiyang China Chinese
Loudi China Chinese
Luohe China Chinese
Linqing China Chinese
Laohekou China Chinese
Linchuan China Chinese
Lhasa China Chinese
Lianyuan China Chinese
Liyang China Chinese
Liling China Chinese
Linhai China Chinese
Larisa Greece Greek
La Habana Cuba Spanish
Lilongwe Malawi Chichewa
León Mexico Spanish
La Paz Mexico Spanish
La Paz Mexico Spanish
Lázaro Cárdenas Mexico Spanish
Lagos de Moreno Mexico Spanish
Lerdo Mexico Spanish
Los Cabos Mexico Spanish
Lerma Mexico Spanish
Las Margaritas Mexico Spanish
Lashio (Lasho) Myanmar Burmese
Lalitapur Nepal Nepali
León Nicaragua Spanish
Lambaré Paraguay Spanish
Lima Peru Spanish
Lisboa Portugal Portuguese
Lódz Poland Polish
Lublin Poland Polish
Legnica Poland Polish
Lyon France French
Le Havre France French
Lille France French
Le Mans France French
Limoges France French
Linköping Sweden Swedish
Lund Sweden Swedish
Leipzig Germany German
Lübeck Germany German
Ludwigshafen am Rhein Germany German
Leverkusen Germany German
Lünen Germany German
Lahti Finland Finnish
Lausanne Switzerland German
Latakia Syria Arabic
Luchou Taiwan Min
Lungtan Taiwan Min
Liberec Czech Republic Czech
Lviv Ukraine Ukrainian
Lugansk Ukraine Ukrainian
Lutsk Ukraine Ukrainian
Lysyt?ansk Ukraine Ukrainian
Lower Hutt New Zealand English
Lida Belarus Belorussian
Los Teques Venezuela Spanish
Lipetsk Russian Federation Russian
Ljubertsy Russian Federation Russian
Leninsk-Kuznetski Russian Federation Russian
Long Xuyen Vietnam Vietnamese
Los Angeles United States English
Las Vegas United States English
Long Beach United States English
Lexington-Fayette United States English
Louisville United States English
Lincoln United States English
Lubbock United States English
Little Rock United States English
Laredo United States English
Lakewood United States English
Lansing United States English
Lancaster United States English
Lafayette United States English
Lowell United States English
Livonia United States English
EXPLAIN
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 PRIMARY City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BNLH join)
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
Name
Vientiane
Riga
Daugavpils
Maseru
Beirut
Tripoli
Monrovia
Tripoli
Bengasi
Misrata
Vilnius
Kaunas
Klaipeda
?iauliai
Panevezys
EXPLAIN
SELECT Country.Name, IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
FROM Country LEFT JOIN CountryLanguage ON
(CountryLanguage.Country=Country.Code AND Language='English')
WHERE
Country.Population > 10000000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country ALL NULL NULL NULL NULL 239 Using where
1 SIMPLE CountryLanguage eq_ref PRIMARY PRIMARY 33 world.Country.Code,const 1 Using where; Using join buffer (flat, BNLH join)
SELECT Country.Name, IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
FROM Country LEFT JOIN CountryLanguage ON
(CountryLanguage.Country=Country.Code AND Language='English')
WHERE
Country.Population > 10000000;
Name IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
Australia 81.2
United Kingdom 97.3
Canada 60.4
United States 86.2
Zimbabwe 2.2
Japan 0.1
South Africa 8.5
Malaysia 1.6
Afghanistan NULL
Netherlands NULL
Algeria NULL
Angola NULL
Argentina NULL
Bangladesh NULL
Belgium NULL
Brazil NULL
Burkina Faso NULL
Chile NULL
Ecuador NULL
Egypt NULL
Spain NULL
Ethiopia NULL
Philippines NULL
Ghana NULL
Guatemala NULL
Indonesia NULL
India NULL
Iraq NULL
Iran NULL
Italy NULL
Yemen NULL
Yugoslavia NULL
Cambodia NULL
Cameroon NULL
Kazakstan NULL
Kenya NULL
China NULL
Colombia NULL
Congo, The Democratic Republic of the NULL
North Korea NULL
South Korea NULL
Greece NULL
Cuba NULL
Madagascar NULL
Malawi NULL
Mali NULL
Morocco NULL
Mexico NULL
Mozambique NULL
Myanmar NULL
Nepal NULL
Niger NULL
Nigeria NULL
Côte d?Ivoire NULL
Pakistan NULL
Peru NULL
Poland NULL
France NULL
Romania NULL
Germany NULL
Saudi Arabia NULL
Somalia NULL
Sri Lanka NULL
Sudan NULL
Syria NULL
Taiwan NULL
Tanzania NULL
Thailand NULL
Czech Republic NULL
Turkey NULL
Uganda NULL
Ukraine NULL
Hungary NULL
Uzbekistan NULL
Belarus NULL
Venezuela NULL
Russian Federation NULL
Vietnam NULL
show variables like 'join_buffer_size';
Variable_name Value
join_buffer_size 131072
set join_cache_level=4;
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 4
EXPLAIN
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 SIMPLE City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BNLH join)
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
EXPLAIN
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE CountryLanguage ALL PRIMARY,Percentage NULL NULL NULL 984 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.CountryLanguage.Country 1 Using where; Using join buffer (flat, BNLH join)
1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using where; Using join buffer (incremental, BNLH join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
Name Name Language
Leiden Netherlands Dutch
La Matanza Argentina Spanish
Lomas de Zamora Argentina Spanish
La Plata Argentina Spanish
Lanús Argentina Spanish
Las Heras Argentina Spanish
La Rioja Argentina Spanish
Liège Belgium Dutch
La Paz Bolivia Spanish
Londrina Brazil Portuguese
Limeira Brazil Portuguese
Lages Brazil Portuguese
Luziânia Brazil Portuguese
Lauro de Freitas Brazil Portuguese
Linhares Brazil Portuguese
London United Kingdom English
Liverpool United Kingdom English
Leeds United Kingdom English
Leicester United Kingdom English
Luton United Kingdom English
Los Angeles Chile Spanish
La Serena Chile Spanish
La Romana Dominican Republic Spanish
Loja Ecuador Spanish
Luxor Egypt Arabic
Las Palmas de Gran Canaria Spain Spanish
L´Hospitalet de Llobregat Spain Spanish
Leganés Spain Spanish
León Spain Spanish
Logroño Spain Spanish
Lleida (Lérida) Spain Spanish
Le-Cap-Haïtien Haiti Haiti Creole
La Ceiba Honduras Spanish
Livorno Italy Italian
Latina Italy Italian
Lecce Italy Italian
La Spezia Italy Italian
Linz Austria German
London Canada English
Laval Canada English
Longueuil Canada English
Lanzhou China Chinese
Luoyang China Chinese
Liuzhou China Chinese
Liaoyang China Chinese
Liupanshui China Chinese
Liaoyuan China Chinese
Lianyungang China Chinese
Leshan China Chinese
Linyi China Chinese
Luzhou China Chinese
Laiwu China Chinese
Liaocheng China Chinese
Laizhou China Chinese
Linfen China Chinese
Liangcheng China Chinese
Longkou China Chinese
Langfang China Chinese
Liu´an China Chinese
Longjing China Chinese
Lengshuijiang China Chinese
Laiyang China Chinese
Longyan China Chinese
Linhe China Chinese
Leiyang China Chinese
Loudi China Chinese
Luohe China Chinese
Linqing China Chinese
Laohekou China Chinese
Linchuan China Chinese
Lhasa China Chinese
Lianyuan China Chinese
Liyang China Chinese
Liling China Chinese
Linhai China Chinese
Larisa Greece Greek
La Habana Cuba Spanish
Lilongwe Malawi Chichewa
León Mexico Spanish
La Paz Mexico Spanish
La Paz Mexico Spanish
Lázaro Cárdenas Mexico Spanish
Lagos de Moreno Mexico Spanish
Lerdo Mexico Spanish
Los Cabos Mexico Spanish
Lerma Mexico Spanish
Las Margaritas Mexico Spanish
Lashio (Lasho) Myanmar Burmese
Lalitapur Nepal Nepali
León Nicaragua Spanish
Lambaré Paraguay Spanish
Lima Peru Spanish
Lisboa Portugal Portuguese
Lódz Poland Polish
Lublin Poland Polish
Legnica Poland Polish
Lyon France French
Le Havre France French
Lille France French
Le Mans France French
Limoges France French
Linköping Sweden Swedish
Lund Sweden Swedish
Leipzig Germany German
Lübeck Germany German
Ludwigshafen am Rhein Germany German
Leverkusen Germany German
Lünen Germany German
Lahti Finland Finnish
Lausanne Switzerland German
Latakia Syria Arabic
Luchou Taiwan Min
Lungtan Taiwan Min
Liberec Czech Republic Czech
Lviv Ukraine Ukrainian
Lugansk Ukraine Ukrainian
Lutsk Ukraine Ukrainian
Lysyt?ansk Ukraine Ukrainian
Lower Hutt New Zealand English
Lida Belarus Belorussian
Los Teques Venezuela Spanish
Lipetsk Russian Federation Russian
Ljubertsy Russian Federation Russian
Leninsk-Kuznetski Russian Federation Russian
Long Xuyen Vietnam Vietnamese
Los Angeles United States English
Las Vegas United States English
Long Beach United States English
Lexington-Fayette United States English
Louisville United States English
Lincoln United States English
Lubbock United States English
Little Rock United States English
Laredo United States English
Lakewood United States English
Lansing United States English
Lancaster United States English
Lafayette United States English
Lowell United States English
Livonia United States English
EXPLAIN
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 PRIMARY City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BNLH join)
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
Name
Vientiane
Riga
Daugavpils
Maseru
Beirut
Tripoli
Monrovia
Tripoli
Bengasi
Misrata
Vilnius
Kaunas
Klaipeda
?iauliai
Panevezys
EXPLAIN
SELECT Country.Name, IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
FROM Country LEFT JOIN CountryLanguage ON
(CountryLanguage.Country=Country.Code AND Language='English')
WHERE
Country.Population > 10000000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country ALL NULL NULL NULL NULL 239 Using where
1 SIMPLE CountryLanguage eq_ref PRIMARY PRIMARY 33 world.Country.Code,const 1 Using where; Using join buffer (flat, BNLH join)
SELECT Country.Name, IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
FROM Country LEFT JOIN CountryLanguage ON
(CountryLanguage.Country=Country.Code AND Language='English')
WHERE
Country.Population > 10000000;
Name IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
Australia 81.2
United Kingdom 97.3
Canada 60.4
United States 86.2
Zimbabwe 2.2
Japan 0.1
South Africa 8.5
Malaysia 1.6
Afghanistan NULL
Netherlands NULL
Algeria NULL
Angola NULL
Argentina NULL
Bangladesh NULL
Belgium NULL
Brazil NULL
Burkina Faso NULL
Chile NULL
Ecuador NULL
Egypt NULL
Spain NULL
Ethiopia NULL
Philippines NULL
Ghana NULL
Guatemala NULL
Indonesia NULL
India NULL
Iraq NULL
Iran NULL
Italy NULL
Yemen NULL
Yugoslavia NULL
Cambodia NULL
Cameroon NULL
Kazakstan NULL
Kenya NULL
China NULL
Colombia NULL
Congo, The Democratic Republic of the NULL
North Korea NULL
South Korea NULL
Greece NULL
Cuba NULL
Madagascar NULL
Malawi NULL
Mali NULL
Morocco NULL
Mexico NULL
Mozambique NULL
Myanmar NULL
Nepal NULL
Niger NULL
Nigeria NULL
Côte d?Ivoire NULL
Pakistan NULL
Peru NULL
Poland NULL
France NULL
Romania NULL
Germany NULL
Saudi Arabia NULL
Somalia NULL
Sri Lanka NULL
Sudan NULL
Syria NULL
Taiwan NULL
Tanzania NULL
Thailand NULL
Czech Republic NULL
Turkey NULL
Uganda NULL
Ukraine NULL
Hungary NULL
Uzbekistan NULL
Belarus NULL
Venezuela NULL
Russian Federation NULL
Vietnam NULL
show variables like 'join_buffer_size';
Variable_name Value
join_buffer_size 131072
set join_cache_level=5;
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 5
EXPLAIN
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 SIMPLE City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BKA join)
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
EXPLAIN
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE CountryLanguage ALL PRIMARY,Percentage NULL NULL NULL 984 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.CountryLanguage.Country 1 Using where; Using join buffer (flat, BKA join)
1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition(BKA); Using where; Using join buffer (flat, BKA join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
Name Name Language
Leiden Netherlands Dutch
La Matanza Argentina Spanish
Lomas de Zamora Argentina Spanish
La Plata Argentina Spanish
Lanús Argentina Spanish
Las Heras Argentina Spanish
La Rioja Argentina Spanish
Liège Belgium Dutch
La Paz Bolivia Spanish
Londrina Brazil Portuguese
Limeira Brazil Portuguese
Lages Brazil Portuguese
Luziânia Brazil Portuguese
Lauro de Freitas Brazil Portuguese
Linhares Brazil Portuguese
London United Kingdom English
Liverpool United Kingdom English
Leeds United Kingdom English
Leicester United Kingdom English
Luton United Kingdom English
Los Angeles Chile Spanish
La Serena Chile Spanish
La Romana Dominican Republic Spanish
Loja Ecuador Spanish
Luxor Egypt Arabic
Las Palmas de Gran Canaria Spain Spanish
L´Hospitalet de Llobregat Spain Spanish
Leganés Spain Spanish
León Spain Spanish
Logroño Spain Spanish
Lleida (Lérida) Spain Spanish
Le-Cap-Haïtien Haiti Haiti Creole
La Ceiba Honduras Spanish
Livorno Italy Italian
Latina Italy Italian
Lecce Italy Italian
La Spezia Italy Italian
Linz Austria German
London Canada English
Laval Canada English
Longueuil Canada English
Lanzhou China Chinese
Luoyang China Chinese
Liuzhou China Chinese
Liaoyang China Chinese
Liupanshui China Chinese
Liaoyuan China Chinese
Lianyungang China Chinese
Leshan China Chinese
Linyi China Chinese
Luzhou China Chinese
Laiwu China Chinese
Liaocheng China Chinese
Laizhou China Chinese
Linfen China Chinese
Liangcheng China Chinese
Longkou China Chinese
Langfang China Chinese
Liu´an China Chinese
Longjing China Chinese
Lengshuijiang China Chinese
Laiyang China Chinese
Longyan China Chinese
Linhe China Chinese
Leiyang China Chinese
Loudi China Chinese
Luohe China Chinese
Linqing China Chinese
Laohekou China Chinese
Linchuan China Chinese
Lhasa China Chinese
Lianyuan China Chinese
Liyang China Chinese
Liling China Chinese
Linhai China Chinese
Larisa Greece Greek
La Habana Cuba Spanish
Lilongwe Malawi Chichewa
León Mexico Spanish
La Paz Mexico Spanish
La Paz Mexico Spanish
Lázaro Cárdenas Mexico Spanish
Lagos de Moreno Mexico Spanish
Lerdo Mexico Spanish
Los Cabos Mexico Spanish
Lerma Mexico Spanish
Las Margaritas Mexico Spanish
Lashio (Lasho) Myanmar Burmese
Lalitapur Nepal Nepali
León Nicaragua Spanish
Lambaré Paraguay Spanish
Lima Peru Spanish
Lisboa Portugal Portuguese
Lódz Poland Polish
Lublin Poland Polish
Legnica Poland Polish
Lyon France French
Le Havre France French
Lille France French
Le Mans France French
Limoges France French
Linköping Sweden Swedish
Lund Sweden Swedish
Leipzig Germany German
Lübeck Germany German
Ludwigshafen am Rhein Germany German
Leverkusen Germany German
Lünen Germany German
Lahti Finland Finnish
Lausanne Switzerland German
Latakia Syria Arabic
Luchou Taiwan Min
Lungtan Taiwan Min
Liberec Czech Republic Czech
Lviv Ukraine Ukrainian
Lugansk Ukraine Ukrainian
Lutsk Ukraine Ukrainian
Lysyt?ansk Ukraine Ukrainian
Lower Hutt New Zealand English
Lida Belarus Belorussian
Los Teques Venezuela Spanish
Lipetsk Russian Federation Russian
Ljubertsy Russian Federation Russian
Leninsk-Kuznetski Russian Federation Russian
Long Xuyen Vietnam Vietnamese
Los Angeles United States English
Las Vegas United States English
Long Beach United States English
Lexington-Fayette United States English
Louisville United States English
Lincoln United States English
Lubbock United States English
Little Rock United States English
Laredo United States English
Lakewood United States English
Lansing United States English
Lancaster United States English
Lafayette United States English
Lowell United States English
Livonia United States English
EXPLAIN
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 PRIMARY City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BKA join)
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
Name
Vientiane
Riga
Daugavpils
Maseru
Beirut
Tripoli
Monrovia
Tripoli
Bengasi
Misrata
Vilnius
Kaunas
Klaipeda
?iauliai
Panevezys
EXPLAIN
SELECT Country.Name, IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
FROM Country LEFT JOIN CountryLanguage ON
(CountryLanguage.Country=Country.Code AND Language='English')
WHERE
Country.Population > 10000000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country ALL NULL NULL NULL NULL 239 Using where
1 SIMPLE CountryLanguage eq_ref PRIMARY PRIMARY 33 world.Country.Code,const 1 Using where; Using join buffer (flat, BKA join)
SELECT Country.Name, IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
FROM Country LEFT JOIN CountryLanguage ON
(CountryLanguage.Country=Country.Code AND Language='English')
WHERE
Country.Population > 10000000;
Name IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
Australia 81.2
United Kingdom 97.3
Canada 60.4
United States 86.2
Zimbabwe 2.2
Japan 0.1
South Africa 8.5
Malaysia 1.6
Afghanistan NULL
Netherlands NULL
Algeria NULL
Angola NULL
Argentina NULL
Bangladesh NULL
Belgium NULL
Brazil NULL
Burkina Faso NULL
Chile NULL
Ecuador NULL
Egypt NULL
Spain NULL
Ethiopia NULL
Philippines NULL
Ghana NULL
Guatemala NULL
Indonesia NULL
India NULL
Iraq NULL
Iran NULL
Italy NULL
Yemen NULL
Yugoslavia NULL
Cambodia NULL
Cameroon NULL
Kazakstan NULL
Kenya NULL
China NULL
Colombia NULL
Congo, The Democratic Republic of the NULL
North Korea NULL
South Korea NULL
Greece NULL
Cuba NULL
Madagascar NULL
Malawi NULL
Mali NULL
Morocco NULL
Mexico NULL
Mozambique NULL
Myanmar NULL
Nepal NULL
Niger NULL
Nigeria NULL
Côte d?Ivoire NULL
Pakistan NULL
Peru NULL
Poland NULL
France NULL
Romania NULL
Germany NULL
Saudi Arabia NULL
Somalia NULL
Sri Lanka NULL
Sudan NULL
Syria NULL
Taiwan NULL
Tanzania NULL
Thailand NULL
Czech Republic NULL
Turkey NULL
Uganda NULL
Ukraine NULL
Hungary NULL
Uzbekistan NULL
Belarus NULL
Venezuela NULL
Russian Federation NULL
Vietnam NULL
set join_cache_level=6;
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 6
EXPLAIN
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 SIMPLE City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BKA join)
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
EXPLAIN
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE CountryLanguage ALL PRIMARY,Percentage NULL NULL NULL 984 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.CountryLanguage.Country 1 Using where; Using join buffer (flat, BKA join)
1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition(BKA); Using where; Using join buffer (incremental, BKA join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
Name Name Language
Leiden Netherlands Dutch
La Matanza Argentina Spanish
Lomas de Zamora Argentina Spanish
La Plata Argentina Spanish
Lanús Argentina Spanish
Las Heras Argentina Spanish
La Rioja Argentina Spanish
Liège Belgium Dutch
La Paz Bolivia Spanish
Londrina Brazil Portuguese
Limeira Brazil Portuguese
Lages Brazil Portuguese
Luziânia Brazil Portuguese
Lauro de Freitas Brazil Portuguese
Linhares Brazil Portuguese
London United Kingdom English
Liverpool United Kingdom English
Leeds United Kingdom English
Leicester United Kingdom English
Luton United Kingdom English
Los Angeles Chile Spanish
La Serena Chile Spanish
La Romana Dominican Republic Spanish
Loja Ecuador Spanish
Luxor Egypt Arabic
Las Palmas de Gran Canaria Spain Spanish
L´Hospitalet de Llobregat Spain Spanish
Leganés Spain Spanish
León Spain Spanish
Logroño Spain Spanish
Lleida (Lérida) Spain Spanish
Le-Cap-Haïtien Haiti Haiti Creole
La Ceiba Honduras Spanish
Livorno Italy Italian
Latina Italy Italian
Lecce Italy Italian
La Spezia Italy Italian
Linz Austria German
London Canada English
Laval Canada English
Longueuil Canada English
Lanzhou China Chinese
Luoyang China Chinese
Liuzhou China Chinese
Liaoyang China Chinese
Liupanshui China Chinese
Liaoyuan China Chinese
Lianyungang China Chinese
Leshan China Chinese
Linyi China Chinese
Luzhou China Chinese
Laiwu China Chinese
Liaocheng China Chinese
Laizhou China Chinese
Linfen China Chinese
Liangcheng China Chinese
Longkou China Chinese
Langfang China Chinese
Liu´an China Chinese
Longjing China Chinese
Lengshuijiang China Chinese
Laiyang China Chinese
Longyan China Chinese
Linhe China Chinese
Leiyang China Chinese
Loudi China Chinese
Luohe China Chinese
Linqing China Chinese
Laohekou China Chinese
Linchuan China Chinese
Lhasa China Chinese
Lianyuan China Chinese
Liyang China Chinese
Liling China Chinese
Linhai China Chinese
Larisa Greece Greek
La Habana Cuba Spanish
Lilongwe Malawi Chichewa
León Mexico Spanish
La Paz Mexico Spanish
La Paz Mexico Spanish
Lázaro Cárdenas Mexico Spanish
Lagos de Moreno Mexico Spanish
Lerdo Mexico Spanish
Los Cabos Mexico Spanish
Lerma Mexico Spanish
Las Margaritas Mexico Spanish
Lashio (Lasho) Myanmar Burmese
Lalitapur Nepal Nepali
León Nicaragua Spanish
Lambaré Paraguay Spanish
Lima Peru Spanish
Lisboa Portugal Portuguese
Lódz Poland Polish
Lublin Poland Polish
Legnica Poland Polish
Lyon France French
Le Havre France French
Lille France French
Le Mans France French
Limoges France French
Linköping Sweden Swedish
Lund Sweden Swedish
Leipzig Germany German
Lübeck Germany German
Ludwigshafen am Rhein Germany German
Leverkusen Germany German
Lünen Germany German
Lahti Finland Finnish
Lausanne Switzerland German
Latakia Syria Arabic
Luchou Taiwan Min
Lungtan Taiwan Min
Liberec Czech Republic Czech
Lviv Ukraine Ukrainian
Lugansk Ukraine Ukrainian
Lutsk Ukraine Ukrainian
Lysyt?ansk Ukraine Ukrainian
Lower Hutt New Zealand English
Lida Belarus Belorussian
Los Teques Venezuela Spanish
Lipetsk Russian Federation Russian
Ljubertsy Russian Federation Russian
Leninsk-Kuznetski Russian Federation Russian
Long Xuyen Vietnam Vietnamese
Los Angeles United States English
Las Vegas United States English
Long Beach United States English
Lexington-Fayette United States English
Louisville United States English
Lincoln United States English
Lubbock United States English
Little Rock United States English
Laredo United States English
Lakewood United States English
Lansing United States English
Lancaster United States English
Lafayette United States English
Lowell United States English
Livonia United States English
EXPLAIN
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 PRIMARY City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BKA join)
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
Name
Vientiane
Riga
Daugavpils
Maseru
Beirut
Tripoli
Monrovia
Tripoli
Bengasi
Misrata
Vilnius
Kaunas
Klaipeda
?iauliai
Panevezys
EXPLAIN
SELECT Country.Name, IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
FROM Country LEFT JOIN CountryLanguage ON
(CountryLanguage.Country=Country.Code AND Language='English')
WHERE
Country.Population > 10000000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country ALL NULL NULL NULL NULL 239 Using where
1 SIMPLE CountryLanguage eq_ref PRIMARY PRIMARY 33 world.Country.Code,const 1 Using where; Using join buffer (flat, BKA join)
SELECT Country.Name, IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
FROM Country LEFT JOIN CountryLanguage ON
(CountryLanguage.Country=Country.Code AND Language='English')
WHERE
Country.Population > 10000000;
Name IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
Australia 81.2
United Kingdom 97.3
Canada 60.4
United States 86.2
Zimbabwe 2.2
Japan 0.1
South Africa 8.5
Malaysia 1.6
Afghanistan NULL
Netherlands NULL
Algeria NULL
Angola NULL
Argentina NULL
Bangladesh NULL
Belgium NULL
Brazil NULL
Burkina Faso NULL
Chile NULL
Ecuador NULL
Egypt NULL
Spain NULL
Ethiopia NULL
Philippines NULL
Ghana NULL
Guatemala NULL
Indonesia NULL
India NULL
Iraq NULL
Iran NULL
Italy NULL
Yemen NULL
Yugoslavia NULL
Cambodia NULL
Cameroon NULL
Kazakstan NULL
Kenya NULL
China NULL
Colombia NULL
Congo, The Democratic Republic of the NULL
North Korea NULL
South Korea NULL
Greece NULL
Cuba NULL
Madagascar NULL
Malawi NULL
Mali NULL
Morocco NULL
Mexico NULL
Mozambique NULL
Myanmar NULL
Nepal NULL
Niger NULL
Nigeria NULL
Côte d?Ivoire NULL
Pakistan NULL
Peru NULL
Poland NULL
France NULL
Romania NULL
Germany NULL
Saudi Arabia NULL
Somalia NULL
Sri Lanka NULL
Sudan NULL
Syria NULL
Taiwan NULL
Tanzania NULL
Thailand NULL
Czech Republic NULL
Turkey NULL
Uganda NULL
Ukraine NULL
Hungary NULL
Uzbekistan NULL
Belarus NULL
Venezuela NULL
Russian Federation NULL
Vietnam NULL
set join_cache_level=7;
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 7
EXPLAIN
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 SIMPLE City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BKAH join)
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
EXPLAIN
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE CountryLanguage ALL PRIMARY,Percentage NULL NULL NULL 984 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.CountryLanguage.Country 1 Using where; Using join buffer (flat, BKAH join)
1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition(BKA); Using where; Using join buffer (flat, BKAH join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
Name Name Language
Leiden Netherlands Dutch
La Matanza Argentina Spanish
Lomas de Zamora Argentina Spanish
La Plata Argentina Spanish
Lanús Argentina Spanish
Las Heras Argentina Spanish
La Rioja Argentina Spanish
Liège Belgium Dutch
La Paz Bolivia Spanish
Londrina Brazil Portuguese
Limeira Brazil Portuguese
Lages Brazil Portuguese
Luziânia Brazil Portuguese
Lauro de Freitas Brazil Portuguese
Linhares Brazil Portuguese
London United Kingdom English
Liverpool United Kingdom English
Leeds United Kingdom English
Leicester United Kingdom English
Luton United Kingdom English
Los Angeles Chile Spanish
La Serena Chile Spanish
La Romana Dominican Republic Spanish
Loja Ecuador Spanish
Luxor Egypt Arabic
Las Palmas de Gran Canaria Spain Spanish
L´Hospitalet de Llobregat Spain Spanish
Leganés Spain Spanish
León Spain Spanish
Logroño Spain Spanish
Lleida (Lérida) Spain Spanish
Le-Cap-Haïtien Haiti Haiti Creole
La Ceiba Honduras Spanish
Livorno Italy Italian
Latina Italy Italian
Lecce Italy Italian
La Spezia Italy Italian
Linz Austria German
London Canada English
Laval Canada English
Longueuil Canada English
Lanzhou China Chinese
Luoyang China Chinese
Liuzhou China Chinese
Liaoyang China Chinese
Liupanshui China Chinese
Liaoyuan China Chinese
Lianyungang China Chinese
Leshan China Chinese
Linyi China Chinese
Luzhou China Chinese
Laiwu China Chinese
Liaocheng China Chinese
Laizhou China Chinese
Linfen China Chinese
Liangcheng China Chinese
Longkou China Chinese
Langfang China Chinese
Liu´an China Chinese
Longjing China Chinese
Lengshuijiang China Chinese
Laiyang China Chinese
Longyan China Chinese
Linhe China Chinese
Leiyang China Chinese
Loudi China Chinese
Luohe China Chinese
Linqing China Chinese
Laohekou China Chinese
Linchuan China Chinese
Lhasa China Chinese
Lianyuan China Chinese
Liyang China Chinese
Liling China Chinese
Linhai China Chinese
Larisa Greece Greek
La Habana Cuba Spanish
Lilongwe Malawi Chichewa
León Mexico Spanish
La Paz Mexico Spanish
La Paz Mexico Spanish
Lázaro Cárdenas Mexico Spanish
Lagos de Moreno Mexico Spanish
Lerdo Mexico Spanish
Los Cabos Mexico Spanish
Lerma Mexico Spanish
Las Margaritas Mexico Spanish
Lashio (Lasho) Myanmar Burmese
Lalitapur Nepal Nepali
León Nicaragua Spanish
Lambaré Paraguay Spanish
Lima Peru Spanish
Lisboa Portugal Portuguese
Lódz Poland Polish
Lublin Poland Polish
Legnica Poland Polish
Lyon France French
Le Havre France French
Lille France French
Le Mans France French
Limoges France French
Linköping Sweden Swedish
Lund Sweden Swedish
Leipzig Germany German
Lübeck Germany German
Ludwigshafen am Rhein Germany German
Leverkusen Germany German
Lünen Germany German
Lahti Finland Finnish
Lausanne Switzerland German
Latakia Syria Arabic
Luchou Taiwan Min
Lungtan Taiwan Min
Liberec Czech Republic Czech
Lviv Ukraine Ukrainian
Lugansk Ukraine Ukrainian
Lutsk Ukraine Ukrainian
Lysyt?ansk Ukraine Ukrainian
Lower Hutt New Zealand English
Lida Belarus Belorussian
Los Teques Venezuela Spanish
Lipetsk Russian Federation Russian
Ljubertsy Russian Federation Russian
Leninsk-Kuznetski Russian Federation Russian
Long Xuyen Vietnam Vietnamese
Los Angeles United States English
Las Vegas United States English
Long Beach United States English
Lexington-Fayette United States English
Louisville United States English
Lincoln United States English
Lubbock United States English
Little Rock United States English
Laredo United States English
Lakewood United States English
Lansing United States English
Lancaster United States English
Lafayette United States English
Lowell United States English
Livonia United States English
EXPLAIN
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 PRIMARY City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BKAH join)
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
Name
Vientiane
Riga
Daugavpils
Maseru
Beirut
Tripoli
Monrovia
Tripoli
Bengasi
Misrata
Vilnius
Kaunas
Klaipeda
?iauliai
Panevezys
EXPLAIN
SELECT Country.Name, IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
FROM Country LEFT JOIN CountryLanguage ON
(CountryLanguage.Country=Country.Code AND Language='English')
WHERE
Country.Population > 10000000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country ALL NULL NULL NULL NULL 239 Using where
1 SIMPLE CountryLanguage eq_ref PRIMARY PRIMARY 33 world.Country.Code,const 1 Using where; Using join buffer (flat, BKAH join)
SELECT Country.Name, IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
FROM Country LEFT JOIN CountryLanguage ON
(CountryLanguage.Country=Country.Code AND Language='English')
WHERE
Country.Population > 10000000;
Name IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
Australia 81.2
United Kingdom 97.3
Canada 60.4
United States 86.2
Zimbabwe 2.2
Japan 0.1
South Africa 8.5
Malaysia 1.6
Afghanistan NULL
Netherlands NULL
Algeria NULL
Angola NULL
Argentina NULL
Bangladesh NULL
Belgium NULL
Brazil NULL
Burkina Faso NULL
Chile NULL
Ecuador NULL
Egypt NULL
Spain NULL
Ethiopia NULL
Philippines NULL
Ghana NULL
Guatemala NULL
Indonesia NULL
India NULL
Iraq NULL
Iran NULL
Italy NULL
Yemen NULL
Yugoslavia NULL
Cambodia NULL
Cameroon NULL
Kazakstan NULL
Kenya NULL
China NULL
Colombia NULL
Congo, The Democratic Republic of the NULL
North Korea NULL
South Korea NULL
Greece NULL
Cuba NULL
Madagascar NULL
Malawi NULL
Mali NULL
Morocco NULL
Mexico NULL
Mozambique NULL
Myanmar NULL
Nepal NULL
Niger NULL
Nigeria NULL
Côte d?Ivoire NULL
Pakistan NULL
Peru NULL
Poland NULL
France NULL
Romania NULL
Germany NULL
Saudi Arabia NULL
Somalia NULL
Sri Lanka NULL
Sudan NULL
Syria NULL
Taiwan NULL
Tanzania NULL
Thailand NULL
Czech Republic NULL
Turkey NULL
Uganda NULL
Ukraine NULL
Hungary NULL
Uzbekistan NULL
Belarus NULL
Venezuela NULL
Russian Federation NULL
Vietnam NULL
set join_cache_level=8;
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 8
EXPLAIN
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 SIMPLE City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BKAH join)
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
EXPLAIN
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE CountryLanguage ALL PRIMARY,Percentage NULL NULL NULL 984 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.CountryLanguage.Country 1 Using where; Using join buffer (flat, BKAH join)
1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition(BKA); Using where; Using join buffer (incremental, BKAH join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
Name Name Language
Leiden Netherlands Dutch
La Matanza Argentina Spanish
Lomas de Zamora Argentina Spanish
La Plata Argentina Spanish
Lanús Argentina Spanish
Las Heras Argentina Spanish
La Rioja Argentina Spanish
Liège Belgium Dutch
La Paz Bolivia Spanish
Londrina Brazil Portuguese
Limeira Brazil Portuguese
Lages Brazil Portuguese
Luziânia Brazil Portuguese
Lauro de Freitas Brazil Portuguese
Linhares Brazil Portuguese
London United Kingdom English
Liverpool United Kingdom English
Leeds United Kingdom English
Leicester United Kingdom English
Luton United Kingdom English
Los Angeles Chile Spanish
La Serena Chile Spanish
La Romana Dominican Republic Spanish
Loja Ecuador Spanish
Luxor Egypt Arabic
Las Palmas de Gran Canaria Spain Spanish
L´Hospitalet de Llobregat Spain Spanish
Leganés Spain Spanish
León Spain Spanish
Logroño Spain Spanish
Lleida (Lérida) Spain Spanish
Le-Cap-Haïtien Haiti Haiti Creole
La Ceiba Honduras Spanish
Livorno Italy Italian
Latina Italy Italian
Lecce Italy Italian
La Spezia Italy Italian
Linz Austria German
London Canada English
Laval Canada English
Longueuil Canada English
Lanzhou China Chinese
Luoyang China Chinese
Liuzhou China Chinese
Liaoyang China Chinese
Liupanshui China Chinese
Liaoyuan China Chinese
Lianyungang China Chinese
Leshan China Chinese
Linyi China Chinese
Luzhou China Chinese
Laiwu China Chinese
Liaocheng China Chinese
Laizhou China Chinese
Linfen China Chinese
Liangcheng China Chinese
Longkou China Chinese
Langfang China Chinese
Liu´an China Chinese
Longjing China Chinese
Lengshuijiang China Chinese
Laiyang China Chinese
Longyan China Chinese
Linhe China Chinese
Leiyang China Chinese
Loudi China Chinese
Luohe China Chinese
Linqing China Chinese
Laohekou China Chinese
Linchuan China Chinese
Lhasa China Chinese
Lianyuan China Chinese
Liyang China Chinese
Liling China Chinese
Linhai China Chinese
Larisa Greece Greek
La Habana Cuba Spanish
Lilongwe Malawi Chichewa
León Mexico Spanish
La Paz Mexico Spanish
La Paz Mexico Spanish
Lázaro Cárdenas Mexico Spanish
Lagos de Moreno Mexico Spanish
Lerdo Mexico Spanish
Los Cabos Mexico Spanish
Lerma Mexico Spanish
Las Margaritas Mexico Spanish
Lashio (Lasho) Myanmar Burmese
Lalitapur Nepal Nepali
León Nicaragua Spanish
Lambaré Paraguay Spanish
Lima Peru Spanish
Lisboa Portugal Portuguese
Lódz Poland Polish
Lublin Poland Polish
Legnica Poland Polish
Lyon France French
Le Havre France French
Lille France French
Le Mans France French
Limoges France French
Linköping Sweden Swedish
Lund Sweden Swedish
Leipzig Germany German
Lübeck Germany German
Ludwigshafen am Rhein Germany German
Leverkusen Germany German
Lünen Germany German
Lahti Finland Finnish
Lausanne Switzerland German
Latakia Syria Arabic
Luchou Taiwan Min
Lungtan Taiwan Min
Liberec Czech Republic Czech
Lviv Ukraine Ukrainian
Lugansk Ukraine Ukrainian
Lutsk Ukraine Ukrainian
Lysyt?ansk Ukraine Ukrainian
Lower Hutt New Zealand English
Lida Belarus Belorussian
Los Teques Venezuela Spanish
Lipetsk Russian Federation Russian
Ljubertsy Russian Federation Russian
Leninsk-Kuznetski Russian Federation Russian
Long Xuyen Vietnam Vietnamese
Los Angeles United States English
Las Vegas United States English
Long Beach United States English
Lexington-Fayette United States English
Louisville United States English
Lincoln United States English
Lubbock United States English
Little Rock United States English
Laredo United States English
Lakewood United States English
Lansing United States English
Lancaster United States English
Lafayette United States English
Lowell United States English
Livonia United States English
EXPLAIN
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 PRIMARY City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BKAH join)
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
Name
Vientiane
Riga
Daugavpils
Maseru
Beirut
Tripoli
Monrovia
Tripoli
Bengasi
Misrata
Vilnius
Kaunas
Klaipeda
?iauliai
Panevezys
EXPLAIN
SELECT Country.Name, IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
FROM Country LEFT JOIN CountryLanguage ON
(CountryLanguage.Country=Country.Code AND Language='English')
WHERE
Country.Population > 10000000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country ALL NULL NULL NULL NULL 239 Using where
1 SIMPLE CountryLanguage eq_ref PRIMARY PRIMARY 33 world.Country.Code,const 1 Using where; Using join buffer (flat, BKAH join)
SELECT Country.Name, IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
FROM Country LEFT JOIN CountryLanguage ON
(CountryLanguage.Country=Country.Code AND Language='English')
WHERE
Country.Population > 10000000;
Name IF(ISNULL(CountryLanguage.Country), NULL, CountryLanguage.Percentage)
Australia 81.2
United Kingdom 97.3
Canada 60.4
United States 86.2
Zimbabwe 2.2
Japan 0.1
South Africa 8.5
Malaysia 1.6
Afghanistan NULL
Netherlands NULL
Algeria NULL
Angola NULL
Argentina NULL
Bangladesh NULL
Belgium NULL
Brazil NULL
Burkina Faso NULL
Chile NULL
Ecuador NULL
Egypt NULL
Spain NULL
Ethiopia NULL
Philippines NULL
Ghana NULL
Guatemala NULL
Indonesia NULL
India NULL
Iraq NULL
Iran NULL
Italy NULL
Yemen NULL
Yugoslavia NULL
Cambodia NULL
Cameroon NULL
Kazakstan NULL
Kenya NULL
China NULL
Colombia NULL
Congo, The Democratic Republic of the NULL
North Korea NULL
South Korea NULL
Greece NULL
Cuba NULL
Madagascar NULL
Malawi NULL
Mali NULL
Morocco NULL
Mexico NULL
Mozambique NULL
Myanmar NULL
Nepal NULL
Niger NULL
Nigeria NULL
Côte d?Ivoire NULL
Pakistan NULL
Peru NULL
Poland NULL
France NULL
Romania NULL
Germany NULL
Saudi Arabia NULL
Somalia NULL
Sri Lanka NULL
Sudan NULL
Syria NULL
Taiwan NULL
Tanzania NULL
Thailand NULL
Czech Republic NULL
Turkey NULL
Uganda NULL
Ukraine NULL
Hungary NULL
Uzbekistan NULL
Belarus NULL
Venezuela NULL
Russian Federation NULL
Vietnam NULL
set join_buffer_size=256;
show variables like 'join_buffer_size';
Variable_name Value
join_buffer_size 256
set join_cache_level=3;
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 3
EXPLAIN
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 SIMPLE City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BNLH join)
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
EXPLAIN
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE CountryLanguage ALL PRIMARY,Percentage NULL NULL NULL 984 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.CountryLanguage.Country 1 Using where; Using join buffer (flat, BNLH join)
1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition; Using where
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
Name Name Language
Leiden Netherlands Dutch
La Matanza Argentina Spanish
Lomas de Zamora Argentina Spanish
La Plata Argentina Spanish
Lanús Argentina Spanish
Las Heras Argentina Spanish
La Rioja Argentina Spanish
Liège Belgium Dutch
La Paz Bolivia Spanish
Londrina Brazil Portuguese
Limeira Brazil Portuguese
Lages Brazil Portuguese
Luziânia Brazil Portuguese
Lauro de Freitas Brazil Portuguese
Linhares Brazil Portuguese
London United Kingdom English
Liverpool United Kingdom English
Leeds United Kingdom English
Leicester United Kingdom English
Luton United Kingdom English
Los Angeles Chile Spanish
La Serena Chile Spanish
La Romana Dominican Republic Spanish
Loja Ecuador Spanish
Luxor Egypt Arabic
Las Palmas de Gran Canaria Spain Spanish
L´Hospitalet de Llobregat Spain Spanish
Leganés Spain Spanish
León Spain Spanish
Logroño Spain Spanish
Lleida (Lérida) Spain Spanish
Le-Cap-Haïtien Haiti Haiti Creole
La Ceiba Honduras Spanish
Livorno Italy Italian
Latina Italy Italian
Lecce Italy Italian
La Spezia Italy Italian
Linz Austria German
London Canada English
Laval Canada English
Longueuil Canada English
Lanzhou China Chinese
Luoyang China Chinese
Liuzhou China Chinese
Liaoyang China Chinese
Liupanshui China Chinese
Liaoyuan China Chinese
Lianyungang China Chinese
Leshan China Chinese
Linyi China Chinese
Luzhou China Chinese
Laiwu China Chinese
Liaocheng China Chinese
Laizhou China Chinese
Linfen China Chinese
Liangcheng China Chinese
Longkou China Chinese
Langfang China Chinese
Liu´an China Chinese
Longjing China Chinese
Lengshuijiang China Chinese
Laiyang China Chinese
Longyan China Chinese
Linhe China Chinese
Leiyang China Chinese
Loudi China Chinese
Luohe China Chinese
Linqing China Chinese
Laohekou China Chinese
Linchuan China Chinese
Lhasa China Chinese
Lianyuan China Chinese
Liyang China Chinese
Liling China Chinese
Linhai China Chinese
Larisa Greece Greek
La Habana Cuba Spanish
Lilongwe Malawi Chichewa
León Mexico Spanish
La Paz Mexico Spanish
La Paz Mexico Spanish
Lázaro Cárdenas Mexico Spanish
Lagos de Moreno Mexico Spanish
Lerdo Mexico Spanish
Los Cabos Mexico Spanish
Lerma Mexico Spanish
Las Margaritas Mexico Spanish
Lashio (Lasho) Myanmar Burmese
Lalitapur Nepal Nepali
León Nicaragua Spanish
Lambaré Paraguay Spanish
Lima Peru Spanish
Lisboa Portugal Portuguese
Lódz Poland Polish
Lublin Poland Polish
Legnica Poland Polish
Lyon France French
Le Havre France French
Lille France French
Le Mans France French
Limoges France French
Linköping Sweden Swedish
Lund Sweden Swedish
Leipzig Germany German
Lübeck Germany German
Ludwigshafen am Rhein Germany German
Leverkusen Germany German
Lünen Germany German
Lahti Finland Finnish
Lausanne Switzerland German
Latakia Syria Arabic
Luchou Taiwan Min
Lungtan Taiwan Min
Liberec Czech Republic Czech
Lviv Ukraine Ukrainian
Lugansk Ukraine Ukrainian
Lutsk Ukraine Ukrainian
Lysyt?ansk Ukraine Ukrainian
Lower Hutt New Zealand English
Lida Belarus Belorussian
Los Teques Venezuela Spanish
Lipetsk Russian Federation Russian
Ljubertsy Russian Federation Russian
Leninsk-Kuznetski Russian Federation Russian
Long Xuyen Vietnam Vietnamese
Los Angeles United States English
Las Vegas United States English
Long Beach United States English
Lexington-Fayette United States English
Louisville United States English
Lincoln United States English
Lubbock United States English
Little Rock United States English
Laredo United States English
Lakewood United States English
Lansing United States English
Lancaster United States English
Lafayette United States English
Lowell United States English
Livonia United States English
EXPLAIN
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 PRIMARY City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BNLH join)
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
Name
Vientiane
Riga
Daugavpils
Maseru
Beirut
Tripoli
Monrovia
Tripoli
Bengasi
Misrata
Vilnius
Kaunas
Klaipeda
?iauliai
Panevezys
set join_cache_level=4;
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 4
EXPLAIN
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 SIMPLE City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BNLH join)
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
EXPLAIN
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE CountryLanguage ALL PRIMARY,Percentage NULL NULL NULL 984 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.CountryLanguage.Country 1 Using where; Using join buffer (flat, BNLH join)
1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using where; Using join buffer (incremental, BNLH join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
Name Name Language
Leiden Netherlands Dutch
La Matanza Argentina Spanish
Lomas de Zamora Argentina Spanish
La Plata Argentina Spanish
Lanús Argentina Spanish
Las Heras Argentina Spanish
La Rioja Argentina Spanish
Liège Belgium Dutch
La Paz Bolivia Spanish
Londrina Brazil Portuguese
Limeira Brazil Portuguese
Lages Brazil Portuguese
Luziânia Brazil Portuguese
Lauro de Freitas Brazil Portuguese
Linhares Brazil Portuguese
London United Kingdom English
Liverpool United Kingdom English
Leeds United Kingdom English
Leicester United Kingdom English
Luton United Kingdom English
Los Angeles Chile Spanish
La Serena Chile Spanish
La Romana Dominican Republic Spanish
Loja Ecuador Spanish
Luxor Egypt Arabic
Las Palmas de Gran Canaria Spain Spanish
L´Hospitalet de Llobregat Spain Spanish
Leganés Spain Spanish
León Spain Spanish
Logroño Spain Spanish
Lleida (Lérida) Spain Spanish
Le-Cap-Haïtien Haiti Haiti Creole
La Ceiba Honduras Spanish
Livorno Italy Italian
Latina Italy Italian
Lecce Italy Italian
La Spezia Italy Italian
Linz Austria German
London Canada English
Laval Canada English
Longueuil Canada English
Lanzhou China Chinese
Luoyang China Chinese
Liuzhou China Chinese
Liaoyang China Chinese
Liupanshui China Chinese
Liaoyuan China Chinese
Lianyungang China Chinese
Leshan China Chinese
Linyi China Chinese
Luzhou China Chinese
Laiwu China Chinese
Liaocheng China Chinese
Laizhou China Chinese
Linfen China Chinese
Liangcheng China Chinese
Longkou China Chinese
Langfang China Chinese
Liu´an China Chinese
Longjing China Chinese
Lengshuijiang China Chinese
Laiyang China Chinese
Longyan China Chinese
Linhe China Chinese
Leiyang China Chinese
Loudi China Chinese
Luohe China Chinese
Linqing China Chinese
Laohekou China Chinese
Linchuan China Chinese
Lhasa China Chinese
Lianyuan China Chinese
Liyang China Chinese
Liling China Chinese
Linhai China Chinese
Larisa Greece Greek
La Habana Cuba Spanish
Lilongwe Malawi Chichewa
León Mexico Spanish
La Paz Mexico Spanish
La Paz Mexico Spanish
Lázaro Cárdenas Mexico Spanish
Lagos de Moreno Mexico Spanish
Lerdo Mexico Spanish
Los Cabos Mexico Spanish
Lerma Mexico Spanish
Las Margaritas Mexico Spanish
Lashio (Lasho) Myanmar Burmese
Lalitapur Nepal Nepali
León Nicaragua Spanish
Lambaré Paraguay Spanish
Lima Peru Spanish
Lisboa Portugal Portuguese
Lódz Poland Polish
Lublin Poland Polish
Legnica Poland Polish
Lyon France French
Le Havre France French
Lille France French
Le Mans France French
Limoges France French
Linköping Sweden Swedish
Lund Sweden Swedish
Leipzig Germany German
Lübeck Germany German
Ludwigshafen am Rhein Germany German
Leverkusen Germany German
Lünen Germany German
Lahti Finland Finnish
Lausanne Switzerland German
Latakia Syria Arabic
Luchou Taiwan Min
Lungtan Taiwan Min
Liberec Czech Republic Czech
Lviv Ukraine Ukrainian
Lugansk Ukraine Ukrainian
Lutsk Ukraine Ukrainian
Lysyt?ansk Ukraine Ukrainian
Lower Hutt New Zealand English
Lida Belarus Belorussian
Los Teques Venezuela Spanish
Lipetsk Russian Federation Russian
Ljubertsy Russian Federation Russian
Leninsk-Kuznetski Russian Federation Russian
Long Xuyen Vietnam Vietnamese
Los Angeles United States English
Las Vegas United States English
Long Beach United States English
Lexington-Fayette United States English
Louisville United States English
Lincoln United States English
Lubbock United States English
Little Rock United States English
Laredo United States English
Lakewood United States English
Lansing United States English
Lancaster United States English
Lafayette United States English
Lowell United States English
Livonia United States English
EXPLAIN
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 PRIMARY City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BNLH join)
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
Name
Vientiane
Riga
Daugavpils
Maseru
Beirut
Tripoli
Monrovia
Tripoli
Bengasi
Misrata
Vilnius
Kaunas
Klaipeda
?iauliai
Panevezys
set join_cache_level=5;
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 5
EXPLAIN
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 SIMPLE City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BKA join)
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
EXPLAIN
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE CountryLanguage ALL PRIMARY,Percentage NULL NULL NULL 984 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.CountryLanguage.Country 1 Using where; Using join buffer (flat, BKA join)
1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition(BKA); Using where; Using join buffer (flat, BKA join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
Name Name Language
Leiden Netherlands Dutch
La Matanza Argentina Spanish
Lomas de Zamora Argentina Spanish
La Plata Argentina Spanish
Lanús Argentina Spanish
Las Heras Argentina Spanish
La Rioja Argentina Spanish
Liège Belgium Dutch
La Paz Bolivia Spanish
Londrina Brazil Portuguese
Limeira Brazil Portuguese
Lages Brazil Portuguese
Luziânia Brazil Portuguese
Lauro de Freitas Brazil Portuguese
Linhares Brazil Portuguese
London United Kingdom English
Liverpool United Kingdom English
Leeds United Kingdom English
Leicester United Kingdom English
Luton United Kingdom English
Los Angeles Chile Spanish
La Serena Chile Spanish
La Romana Dominican Republic Spanish
Loja Ecuador Spanish
Luxor Egypt Arabic
Las Palmas de Gran Canaria Spain Spanish
L´Hospitalet de Llobregat Spain Spanish
Leganés Spain Spanish
León Spain Spanish
Logroño Spain Spanish
Lleida (Lérida) Spain Spanish
Le-Cap-Haïtien Haiti Haiti Creole
La Ceiba Honduras Spanish
Livorno Italy Italian
Latina Italy Italian
Lecce Italy Italian
La Spezia Italy Italian
Linz Austria German
London Canada English
Laval Canada English
Longueuil Canada English
Lanzhou China Chinese
Luoyang China Chinese
Liuzhou China Chinese
Liaoyang China Chinese
Liupanshui China Chinese
Liaoyuan China Chinese
Lianyungang China Chinese
Leshan China Chinese
Linyi China Chinese
Luzhou China Chinese
Laiwu China Chinese
Liaocheng China Chinese
Laizhou China Chinese
Linfen China Chinese
Liangcheng China Chinese
Longkou China Chinese
Langfang China Chinese
Liu´an China Chinese
Longjing China Chinese
Lengshuijiang China Chinese
Laiyang China Chinese
Longyan China Chinese
Linhe China Chinese
Leiyang China Chinese
Loudi China Chinese
Luohe China Chinese
Linqing China Chinese
Laohekou China Chinese
Linchuan China Chinese
Lhasa China Chinese
Lianyuan China Chinese
Liyang China Chinese
Liling China Chinese
Linhai China Chinese
Larisa Greece Greek
La Habana Cuba Spanish
Lilongwe Malawi Chichewa
León Mexico Spanish
La Paz Mexico Spanish
La Paz Mexico Spanish
Lázaro Cárdenas Mexico Spanish
Lagos de Moreno Mexico Spanish
Lerdo Mexico Spanish
Los Cabos Mexico Spanish
Lerma Mexico Spanish
Las Margaritas Mexico Spanish
Lashio (Lasho) Myanmar Burmese
Lalitapur Nepal Nepali
León Nicaragua Spanish
Lambaré Paraguay Spanish
Lima Peru Spanish
Lisboa Portugal Portuguese
Lódz Poland Polish
Lublin Poland Polish
Legnica Poland Polish
Lyon France French
Le Havre France French
Lille France French
Le Mans France French
Limoges France French
Linköping Sweden Swedish
Lund Sweden Swedish
Leipzig Germany German
Lübeck Germany German
Ludwigshafen am Rhein Germany German
Leverkusen Germany German
Lünen Germany German
Lahti Finland Finnish
Lausanne Switzerland German
Latakia Syria Arabic
Luchou Taiwan Min
Lungtan Taiwan Min
Liberec Czech Republic Czech
Lviv Ukraine Ukrainian
Lugansk Ukraine Ukrainian
Lutsk Ukraine Ukrainian
Lysyt?ansk Ukraine Ukrainian
Lower Hutt New Zealand English
Lida Belarus Belorussian
Los Teques Venezuela Spanish
Lipetsk Russian Federation Russian
Ljubertsy Russian Federation Russian
Leninsk-Kuznetski Russian Federation Russian
Long Xuyen Vietnam Vietnamese
Los Angeles United States English
Las Vegas United States English
Long Beach United States English
Lexington-Fayette United States English
Louisville United States English
Lincoln United States English
Lubbock United States English
Little Rock United States English
Laredo United States English
Lakewood United States English
Lansing United States English
Lancaster United States English
Lafayette United States English
Lowell United States English
Livonia United States English
EXPLAIN
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 PRIMARY City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BKA join)
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
Name
Vientiane
Riga
Daugavpils
Maseru
Beirut
Tripoli
Monrovia
Tripoli
Bengasi
Misrata
Vilnius
Kaunas
Klaipeda
?iauliai
Panevezys
set join_cache_level=6;
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 6
EXPLAIN
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 SIMPLE City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BKA join)
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
EXPLAIN
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE CountryLanguage ALL PRIMARY,Percentage NULL NULL NULL 984 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.CountryLanguage.Country 1 Using where; Using join buffer (flat, BKA join)
1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition(BKA); Using where; Using join buffer (incremental, BKA join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
Name Name Language
Leiden Netherlands Dutch
La Matanza Argentina Spanish
Lomas de Zamora Argentina Spanish
La Plata Argentina Spanish
Lanús Argentina Spanish
Las Heras Argentina Spanish
La Rioja Argentina Spanish
Liège Belgium Dutch
La Paz Bolivia Spanish
Londrina Brazil Portuguese
Limeira Brazil Portuguese
Lages Brazil Portuguese
Luziânia Brazil Portuguese
Lauro de Freitas Brazil Portuguese
Linhares Brazil Portuguese
London United Kingdom English
Liverpool United Kingdom English
Leeds United Kingdom English
Leicester United Kingdom English
Luton United Kingdom English
Los Angeles Chile Spanish
La Serena Chile Spanish
La Romana Dominican Republic Spanish
Loja Ecuador Spanish
Luxor Egypt Arabic
Las Palmas de Gran Canaria Spain Spanish
L´Hospitalet de Llobregat Spain Spanish
Leganés Spain Spanish
León Spain Spanish
Logroño Spain Spanish
Lleida (Lérida) Spain Spanish
Le-Cap-Haïtien Haiti Haiti Creole
La Ceiba Honduras Spanish
Livorno Italy Italian
Latina Italy Italian
Lecce Italy Italian
La Spezia Italy Italian
Linz Austria German
London Canada English
Laval Canada English
Longueuil Canada English
Lanzhou China Chinese
Luoyang China Chinese
Liuzhou China Chinese
Liaoyang China Chinese
Liupanshui China Chinese
Liaoyuan China Chinese
Lianyungang China Chinese
Leshan China Chinese
Linyi China Chinese
Luzhou China Chinese
Laiwu China Chinese
Liaocheng China Chinese
Laizhou China Chinese
Linfen China Chinese
Liangcheng China Chinese
Longkou China Chinese
Langfang China Chinese
Liu´an China Chinese
Longjing China Chinese
Lengshuijiang China Chinese
Laiyang China Chinese
Longyan China Chinese
Linhe China Chinese
Leiyang China Chinese
Loudi China Chinese
Luohe China Chinese
Linqing China Chinese
Laohekou China Chinese
Linchuan China Chinese
Lhasa China Chinese
Lianyuan China Chinese
Liyang China Chinese
Liling China Chinese
Linhai China Chinese
Larisa Greece Greek
La Habana Cuba Spanish
Lilongwe Malawi Chichewa
León Mexico Spanish
La Paz Mexico Spanish
La Paz Mexico Spanish
Lázaro Cárdenas Mexico Spanish
Lagos de Moreno Mexico Spanish
Lerdo Mexico Spanish
Los Cabos Mexico Spanish
Lerma Mexico Spanish
Las Margaritas Mexico Spanish
Lashio (Lasho) Myanmar Burmese
Lalitapur Nepal Nepali
León Nicaragua Spanish
Lambaré Paraguay Spanish
Lima Peru Spanish
Lisboa Portugal Portuguese
Lódz Poland Polish
Lublin Poland Polish
Legnica Poland Polish
Lyon France French
Le Havre France French
Lille France French
Le Mans France French
Limoges France French
Linköping Sweden Swedish
Lund Sweden Swedish
Leipzig Germany German
Lübeck Germany German
Ludwigshafen am Rhein Germany German
Leverkusen Germany German
Lünen Germany German
Lahti Finland Finnish
Lausanne Switzerland German
Latakia Syria Arabic
Luchou Taiwan Min
Lungtan Taiwan Min
Liberec Czech Republic Czech
Lviv Ukraine Ukrainian
Lugansk Ukraine Ukrainian
Lutsk Ukraine Ukrainian
Lysyt?ansk Ukraine Ukrainian
Lower Hutt New Zealand English
Lida Belarus Belorussian
Los Teques Venezuela Spanish
Lipetsk Russian Federation Russian
Ljubertsy Russian Federation Russian
Leninsk-Kuznetski Russian Federation Russian
Long Xuyen Vietnam Vietnamese
Los Angeles United States English
Las Vegas United States English
Long Beach United States English
Lexington-Fayette United States English
Louisville United States English
Lincoln United States English
Lubbock United States English
Little Rock United States English
Laredo United States English
Lakewood United States English
Lansing United States English
Lancaster United States English
Lafayette United States English
Lowell United States English
Livonia United States English
EXPLAIN
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 PRIMARY City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BKA join)
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
Name
Vientiane
Riga
Daugavpils
Maseru
Beirut
Tripoli
Monrovia
Tripoli
Bengasi
Misrata
Vilnius
Kaunas
Klaipeda
?iauliai
Panevezys
set join_cache_level=7;
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 7
EXPLAIN
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 SIMPLE City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BKAH join)
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
EXPLAIN
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE CountryLanguage ALL PRIMARY,Percentage NULL NULL NULL 984 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.CountryLanguage.Country 1 Using where; Using join buffer (flat, BKAH join)
1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition(BKA); Using where; Using join buffer (flat, BKAH join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
Name Name Language
Leiden Netherlands Dutch
La Matanza Argentina Spanish
Lomas de Zamora Argentina Spanish
La Plata Argentina Spanish
Lanús Argentina Spanish
Las Heras Argentina Spanish
La Rioja Argentina Spanish
Liège Belgium Dutch
La Paz Bolivia Spanish
Londrina Brazil Portuguese
Limeira Brazil Portuguese
Lages Brazil Portuguese
Luziânia Brazil Portuguese
Lauro de Freitas Brazil Portuguese
Linhares Brazil Portuguese
London United Kingdom English
Liverpool United Kingdom English
Leeds United Kingdom English
Leicester United Kingdom English
Luton United Kingdom English
Los Angeles Chile Spanish
La Serena Chile Spanish
La Romana Dominican Republic Spanish
Loja Ecuador Spanish
Luxor Egypt Arabic
Las Palmas de Gran Canaria Spain Spanish
L´Hospitalet de Llobregat Spain Spanish
Leganés Spain Spanish
León Spain Spanish
Logroño Spain Spanish
Lleida (Lérida) Spain Spanish
Le-Cap-Haïtien Haiti Haiti Creole
La Ceiba Honduras Spanish
Livorno Italy Italian
Latina Italy Italian
Lecce Italy Italian
La Spezia Italy Italian
Linz Austria German
London Canada English
Laval Canada English
Longueuil Canada English
Lanzhou China Chinese
Luoyang China Chinese
Liuzhou China Chinese
Liaoyang China Chinese
Liupanshui China Chinese
Liaoyuan China Chinese
Lianyungang China Chinese
Leshan China Chinese
Linyi China Chinese
Luzhou China Chinese
Laiwu China Chinese
Liaocheng China Chinese
Laizhou China Chinese
Linfen China Chinese
Liangcheng China Chinese
Longkou China Chinese
Langfang China Chinese
Liu´an China Chinese
Longjing China Chinese
Lengshuijiang China Chinese
Laiyang China Chinese
Longyan China Chinese
Linhe China Chinese
Leiyang China Chinese
Loudi China Chinese
Luohe China Chinese
Linqing China Chinese
Laohekou China Chinese
Linchuan China Chinese
Lhasa China Chinese
Lianyuan China Chinese
Liyang China Chinese
Liling China Chinese
Linhai China Chinese
Larisa Greece Greek
La Habana Cuba Spanish
Lilongwe Malawi Chichewa
León Mexico Spanish
La Paz Mexico Spanish
La Paz Mexico Spanish
Lázaro Cárdenas Mexico Spanish
Lagos de Moreno Mexico Spanish
Lerdo Mexico Spanish
Los Cabos Mexico Spanish
Lerma Mexico Spanish
Las Margaritas Mexico Spanish
Lashio (Lasho) Myanmar Burmese
Lalitapur Nepal Nepali
León Nicaragua Spanish
Lambaré Paraguay Spanish
Lima Peru Spanish
Lisboa Portugal Portuguese
Lódz Poland Polish
Lublin Poland Polish
Legnica Poland Polish
Lyon France French
Le Havre France French
Lille France French
Le Mans France French
Limoges France French
Linköping Sweden Swedish
Lund Sweden Swedish
Leipzig Germany German
Lübeck Germany German
Ludwigshafen am Rhein Germany German
Leverkusen Germany German
Lünen Germany German
Lahti Finland Finnish
Lausanne Switzerland German
Latakia Syria Arabic
Luchou Taiwan Min
Lungtan Taiwan Min
Liberec Czech Republic Czech
Lviv Ukraine Ukrainian
Lugansk Ukraine Ukrainian
Lutsk Ukraine Ukrainian
Lysyt?ansk Ukraine Ukrainian
Lower Hutt New Zealand English
Lida Belarus Belorussian
Los Teques Venezuela Spanish
Lipetsk Russian Federation Russian
Ljubertsy Russian Federation Russian
Leninsk-Kuznetski Russian Federation Russian
Long Xuyen Vietnam Vietnamese
Los Angeles United States English
Las Vegas United States English
Long Beach United States English
Lexington-Fayette United States English
Louisville United States English
Lincoln United States English
Lubbock United States English
Little Rock United States English
Laredo United States English
Lakewood United States English
Lansing United States English
Lancaster United States English
Lafayette United States English
Lowell United States English
Livonia United States English
EXPLAIN
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 PRIMARY City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BKAH join)
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
Name
Vientiane
Riga
Daugavpils
Maseru
Beirut
Tripoli
Monrovia
Tripoli
Bengasi
Misrata
Vilnius
Kaunas
Klaipeda
?iauliai
Panevezys
set join_cache_level=8;
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 8
EXPLAIN
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 SIMPLE City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BKAH join)
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
EXPLAIN
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE CountryLanguage ALL PRIMARY,Percentage NULL NULL NULL 984 Using where
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.CountryLanguage.Country 1 Using where; Using join buffer (flat, BKAH join)
1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition(BKA); Using where; Using join buffer (incremental, BKAH join)
SELECT City.Name, Country.Name, CountryLanguage.Language
FROM City,Country,CountryLanguage
WHERE City.Country=Country.Code AND
CountryLanguage.Country=Country.Code AND
City.Name LIKE 'L%' AND Country.Population > 3000000 AND
CountryLanguage.Percentage > 50;
Name Name Language
Leiden Netherlands Dutch
La Matanza Argentina Spanish
Lomas de Zamora Argentina Spanish
La Plata Argentina Spanish
Lanús Argentina Spanish
Las Heras Argentina Spanish
La Rioja Argentina Spanish
Liège Belgium Dutch
La Paz Bolivia Spanish
Londrina Brazil Portuguese
Limeira Brazil Portuguese
Lages Brazil Portuguese
Luziânia Brazil Portuguese
Lauro de Freitas Brazil Portuguese
Linhares Brazil Portuguese
London United Kingdom English
Liverpool United Kingdom English
Leeds United Kingdom English
Leicester United Kingdom English
Luton United Kingdom English
Los Angeles Chile Spanish
La Serena Chile Spanish
La Romana Dominican Republic Spanish
Loja Ecuador Spanish
Luxor Egypt Arabic
Las Palmas de Gran Canaria Spain Spanish
L´Hospitalet de Llobregat Spain Spanish
Leganés Spain Spanish
León Spain Spanish
Logroño Spain Spanish
Lleida (Lérida) Spain Spanish
Le-Cap-Haïtien Haiti Haiti Creole
La Ceiba Honduras Spanish
Livorno Italy Italian
Latina Italy Italian
Lecce Italy Italian
La Spezia Italy Italian
Linz Austria German
London Canada English
Laval Canada English
Longueuil Canada English
Lanzhou China Chinese
Luoyang China Chinese
Liuzhou China Chinese
Liaoyang China Chinese
Liupanshui China Chinese
Liaoyuan China Chinese
Lianyungang China Chinese
Leshan China Chinese
Linyi China Chinese
Luzhou China Chinese
Laiwu China Chinese
Liaocheng China Chinese
Laizhou China Chinese
Linfen China Chinese
Liangcheng China Chinese
Longkou China Chinese
Langfang China Chinese
Liu´an China Chinese
Longjing China Chinese
Lengshuijiang China Chinese
Laiyang China Chinese
Longyan China Chinese
Linhe China Chinese
Leiyang China Chinese
Loudi China Chinese
Luohe China Chinese
Linqing China Chinese
Laohekou China Chinese
Linchuan China Chinese
Lhasa China Chinese
Lianyuan China Chinese
Liyang China Chinese
Liling China Chinese
Linhai China Chinese
Larisa Greece Greek
La Habana Cuba Spanish
Lilongwe Malawi Chichewa
León Mexico Spanish
La Paz Mexico Spanish
La Paz Mexico Spanish
Lázaro Cárdenas Mexico Spanish
Lagos de Moreno Mexico Spanish
Lerdo Mexico Spanish
Los Cabos Mexico Spanish
Lerma Mexico Spanish
Las Margaritas Mexico Spanish
Lashio (Lasho) Myanmar Burmese
Lalitapur Nepal Nepali
León Nicaragua Spanish
Lambaré Paraguay Spanish
Lima Peru Spanish
Lisboa Portugal Portuguese
Lódz Poland Polish
Lublin Poland Polish
Legnica Poland Polish
Lyon France French
Le Havre France French
Lille France French
Le Mans France French
Limoges France French
Linköping Sweden Swedish
Lund Sweden Swedish
Leipzig Germany German
Lübeck Germany German
Ludwigshafen am Rhein Germany German
Leverkusen Germany German
Lünen Germany German
Lahti Finland Finnish
Lausanne Switzerland German
Latakia Syria Arabic
Luchou Taiwan Min
Lungtan Taiwan Min
Liberec Czech Republic Czech
Lviv Ukraine Ukrainian
Lugansk Ukraine Ukrainian
Lutsk Ukraine Ukrainian
Lysyt?ansk Ukraine Ukrainian
Lower Hutt New Zealand English
Lida Belarus Belorussian
Los Teques Venezuela Spanish
Lipetsk Russian Federation Russian
Ljubertsy Russian Federation Russian
Leninsk-Kuznetski Russian Federation Russian
Long Xuyen Vietnam Vietnamese
Los Angeles United States English
Las Vegas United States English
Long Beach United States English
Lexington-Fayette United States English
Louisville United States English
Lincoln United States English
Lubbock United States English
Little Rock United States English
Laredo United States English
Lakewood United States English
Lansing United States English
Lancaster United States English
Lafayette United States English
Lowell United States English
Livonia United States English
EXPLAIN
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY Country range PRIMARY,Name Name 52 NULL 10 Using index condition; Using MRR
1 PRIMARY City ref Population,Country Country 3 world.Country.Code 18 Using where; Using join buffer (flat, BKAH join)
SELECT Name FROM City
WHERE City.Country IN (SELECT Code FROM Country WHERE Country.Name LIKE 'L%') AND
City.Population > 100000;
Name
Vientiane
Riga
Daugavpils
Maseru
Beirut
Tripoli
Monrovia
Tripoli
Bengasi
Misrata
Vilnius
Kaunas
Klaipeda
?iauliai
Panevezys
set join_cache_level=default;
set join_buffer_size=default;
show variables like 'join_buffer_size';
Variable_name Value
join_buffer_size 131072
show variables like 'join_cache_level';
Variable_name Value
join_cache_level 1
set join_cache_level=1;
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND City.Population > 3000000;
Name Name
Sydney Australia
Dhaka Bangladesh
São Paulo Brazil
Rio de Janeiro Brazil
London United Kingdom
Santiago de Chile Chile
Cairo Egypt
Alexandria Egypt
Jakarta Indonesia
Mumbai (Bombay) India
Delhi India
Calcutta [Kolkata] India
Chennai (Madras) India
Baghdad Iraq
Teheran Iran
Tokyo Japan
Jokohama [Yokohama] Japan
Shanghai China
Peking China
Chongqing China
Tianjin China
Wuhan China
Harbin China
Shenyang China
Kanton [Guangzhou] China
Chengdu China
Santafé de Bogotá Colombia
Kinshasa Congo, The Democratic Republic of the
Seoul South Korea
Pusan South Korea
Ciudad de México Mexico
Rangoon (Yangon) Myanmar
Karachi Pakistan
Lahore Pakistan
Lima Peru
Berlin Germany
Riyadh Saudi Arabia
Singapore Singapore
Bangkok Thailand
Istanbul Turkey
Ankara Turkey
Moscow Russian Federation
St Petersburg Russian Federation
Ho Chi Minh City Vietnam
New York United States
Los Angeles United States
set join_cache_level=8;
set join_buffer_size=384;
EXPLAIN
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND City.Population > 3000000;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE City range Population,Country Population 4 NULL # Using index condition; Using MRR
1 SIMPLE Country eq_ref PRIMARY PRIMARY 3 world.City.Country # Using join buffer (flat, BKAH join)
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND City.Population > 3000000;
Name Name
Alexandria Egypt
Ankara Turkey
Baghdad Iraq
Bangkok Thailand
Berlin Germany
Cairo Egypt
Calcutta [Kolkata] India
Chengdu China
Chennai (Madras) India
Chongqing China
Ciudad de México Mexico
Delhi India
Dhaka Bangladesh
Harbin China
Ho Chi Minh City Vietnam
Istanbul Turkey
Jakarta Indonesia
Jokohama [Yokohama] Japan
Kanton [Guangzhou] China
Karachi Pakistan
Kinshasa Congo, The Democratic Republic of the
Lahore Pakistan
Lima Peru
London United Kingdom
Los Angeles United States
Moscow Russian Federation
Mumbai (Bombay) India
New York United States
Peking China
Pusan South Korea
Rangoon (Yangon) Myanmar
Rio de Janeiro Brazil
Riyadh Saudi Arabia
Santafé de Bogotá Colombia
Santiago de Chile Chile
Seoul South Korea
Shanghai China
Shenyang China
Singapore Singapore
St Petersburg Russian Federation
Sydney Australia
São Paulo Brazil
Teheran Iran
Tianjin China
Tokyo Japan
Wuhan China
set join_buffer_size=default;
set join_cache_level=6;
ALTER TABLE Country MODIFY Name varchar(52) NOT NULL default '';
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
ALTER TABLE Country MODIFY Name varchar(300) NOT NULL default '';
SELECT City.Name, Country.Name FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name
Vientiane Laos
Riga Latvia
Daugavpils Latvia
Maseru Lesotho
Beirut Lebanon
Tripoli Lebanon
Monrovia Liberia
Tripoli Libyan Arab Jamahiriya
Bengasi Libyan Arab Jamahiriya
Misrata Libyan Arab Jamahiriya
Vilnius Lithuania
Kaunas Lithuania
Klaipeda Lithuania
?iauliai Lithuania
Panevezys Lithuania
ALTER TABLE Country ADD COLUMN PopulationBar text;
UPDATE Country
SET PopulationBar=REPEAT('x', CAST(Population/100000 AS unsigned int));
SELECT City.Name, Country.Name, Country.PopulationBar FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name PopulationBar
Vientiane Laos xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Riga Latvia xxxxxxxxxxxxxxxxxxxxxxxx
Daugavpils Latvia xxxxxxxxxxxxxxxxxxxxxxxx
Maseru Lesotho xxxxxxxxxxxxxxxxxxxxxx
Beirut Lebanon xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Tripoli Lebanon xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Monrovia Liberia xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Tripoli Libyan Arab Jamahiriya xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Bengasi Libyan Arab Jamahiriya xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Misrata Libyan Arab Jamahiriya xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Vilnius Lithuania xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Kaunas Lithuania xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Klaipeda Lithuania xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
?iauliai Lithuania xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Panevezys Lithuania xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
set join_buffer_size=256;
SELECT City.Name, Country.Name, Country.PopulationBar FROM City,Country
WHERE City.Country=Country.Code AND
Country.Name LIKE 'L%' AND City.Population > 100000;
Name Name PopulationBar
Vientiane Laos xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Riga Latvia xxxxxxxxxxxxxxxxxxxxxxxx
Daugavpils Latvia xxxxxxxxxxxxxxxxxxxxxxxx
Maseru Lesotho xxxxxxxxxxxxxxxxxxxxxx
Beirut Lebanon xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Tripoli Lebanon xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Monrovia Liberia xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Tripoli Libyan Arab Jamahiriya xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Bengasi Libyan Arab Jamahiriya xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Misrata Libyan Arab Jamahiriya xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Vilnius Lithuania xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Kaunas Lithuania xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Klaipeda Lithuania xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
?iauliai Lithuania xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Panevezys Lithuania xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
set join_cache_level=default;
set join_buffer_size=default;
DROP DATABASE world;
use test;
CREATE TABLE t1(
affiliatetometaid int NOT NULL default '0',
uniquekey int NOT NULL default '0',
metaid int NOT NULL default '0',
affiliateid int NOT NULL default '0',
xml text,
isactive char(1) NOT NULL default 'Y',
PRIMARY KEY (affiliatetometaid)
);
CREATE UNIQUE INDEX t1_uniquekey ON t1(uniquekey);
CREATE INDEX t1_affiliateid ON t1(affiliateid);
CREATE INDEX t1_metaid on t1 (metaid);
INSERT INTO t1 VALUES
(1616, 1571693233, 1391, 2, NULL, 'Y'), (1943, 1993216749, 1726, 2, NULL, 'Y');
CREATE TABLE t2(
metaid int NOT NULL default '0',
name varchar(80) NOT NULL default '',
dateadded timestamp NOT NULL ,
xml text,
status int default NULL,
origin int default NULL,
gid int NOT NULL default '1',
formattypeid int default NULL,
PRIMARY KEY (metaid)
);
CREATE INDEX t2_status ON t2(status);
CREATE INDEX t2_gid ON t2(gid);
CREATE INDEX t2_formattypeid ON t2(formattypeid);
INSERT INTO t2 VALUES
(1391, "I Just Died", "2003-10-02 10:07:37", "", 1, NULL, 3, NULL),
(1726, "Me, Myself & I", "2003-12-05 11:24:36", " ", 1, NULL, 3, NULL);
CREATE TABLE t3(
mediaid int NOT NULL ,
metaid int NOT NULL default '0',
formatid int NOT NULL default '0',
status int default NULL,
path varchar(100) NOT NULL default '',
datemodified timestamp NOT NULL ,
resourcetype int NOT NULL default '1',
parameters text,
signature int default NULL,
quality int NOT NULL default '255',
PRIMARY KEY (mediaid)
);
CREATE INDEX t3_metaid ON t3(metaid);
CREATE INDEX t3_formatid ON t3(formatid);
CREATE INDEX t3_status ON t3(status);
CREATE INDEX t3_metaidformatid ON t3(metaid,formatid);
CREATE INDEX t3_signature ON t3(signature);
CREATE INDEX t3_quality ON t3(quality);
INSERT INTO t3 VALUES
(6, 4, 8, 0, "010101_anastacia_spmidi.mid", "2004-03-16 13:40:00", 1, NULL, NULL, 255),
(3343, 3, 8, 1, "010102_4VN4bsPwnxRQUJW5Zp1RhG2IL9vvl_8.mid", "2004-03-16 13:40:00", 1, NULL, NULL, 255);
CREATE TABLE t4(
formatid int NOT NULL ,
name varchar(60) NOT NULL default '',
formatclassid int NOT NULL default '0',
mime varchar(60) default NULL,
extension varchar(10) default NULL,
priority int NOT NULL default '0',
canaddtocapability char(1) NOT NULL default 'Y',
PRIMARY KEY (formatid)
);
CREATE INDEX t4_formatclassid ON t4(formatclassid);
CREATE INDEX t4_formats_idx ON t4(canaddtocapability);
INSERT INTO t4 VALUES
(19, "XHTML", 11, "text/html", "xhtml", 10, 'Y'),
(54, "AMR (wide band)", 13, "audio/amr-wb", "awb", 0, 'Y');
CREATE TABLE t5(
formatclassid int NOT NULL ,
name varchar(60) NOT NULL default '',
priority int NOT NULL default '0',
formattypeid int NOT NULL default '0',
PRIMARY KEY (formatclassid)
);
CREATE INDEX t5_formattypeid on t5(formattypeid);
INSERT INTO t5 VALUES
(11, "Info", 0, 4), (13, "Digital Audio", 0, 2);
CREATE TABLE t6(
formattypeid int NOT NULL ,
name varchar(60) NOT NULL default '',
priority int default NULL,
PRIMARY KEY (formattypeid)
);
INSERT INTO t6 VALUES
(2, "Ringtones", 0);
CREATE TABLE t7(
metaid int NOT NULL default '0',
artistid int NOT NULL default '0',
PRIMARY KEY (metaid,artistid)
);
INSERT INTO t7 VALUES
(4, 5), (3, 4);
CREATE TABLE t8(
artistid int NOT NULL ,
name varchar(80) NOT NULL default '',
PRIMARY KEY (artistid)
);
INSERT INTO t8 VALUES
(5, "Anastacia"), (4, "John Mayer");
CREATE TABLE t9(
subgenreid int NOT NULL default '0',
metaid int NOT NULL default '0',
PRIMARY KEY (subgenreid,metaid)
) ;
CREATE INDEX t9_subgenreid ON t9(subgenreid);
CREATE INDEX t9_metaid ON t9(metaid);
INSERT INTO t9 VALUES
(138, 4), (31, 3);
CREATE TABLE t10(
subgenreid int NOT NULL ,
genreid int NOT NULL default '0',
name varchar(80) NOT NULL default '',
PRIMARY KEY (subgenreid)
) ;
CREATE INDEX t10_genreid ON t10(genreid);
INSERT INTO t10 VALUES
(138, 19, ''), (31, 3, '');
CREATE TABLE t11(
genreid int NOT NULL default '0',
name char(80) NOT NULL default '',
priority int NOT NULL default '0',
masterclip char(1) default NULL,
PRIMARY KEY (genreid)
) ;
CREATE INDEX t11_masterclip ON t11( masterclip);
INSERT INTO t11 VALUES
(19, "Pop & Dance", 95, 'Y'), (3, "Rock & Alternative", 100, 'Y');
set join_cache_level=6;
EXPLAIN
SELECT t1.uniquekey, t1.xml AS affiliateXml,
t8.name AS artistName, t8.artistid,
t11.name AS genreName, t11.genreid, t11.priority AS genrePriority,
t10.subgenreid, t10.name AS subgenreName,
t2.name AS metaName, t2.metaid, t2.xml AS metaXml,
t4.priority + t5.priority + t6.priority AS overallPriority,
t3.path AS path, t3.mediaid,
t4.formatid, t4.name AS formatName,
t5.formatclassid, t5.name AS formatclassName,
t6.formattypeid, t6.name AS formattypeName
FROM t1, t2, t3, t4, t5, t6, t7, t8, t9, t10, t11
WHERE t7.metaid = t2.metaid AND t7.artistid = t8.artistid AND
t9.metaid = t2.metaid AND t9.subgenreid = t10.subgenreid AND
t10.genreid = t11.genreid AND t3.metaid = t2.metaid AND
t3.formatid = t4.formatid AND t4.formatclassid = t5.formatclassid AND
t4.canaddtocapability = 'Y' AND t5.formattypeid = t6.formattypeid AND
t6.formattypeid IN (2) AND (t3.formatid IN (31, 8, 76)) AND
t1.metaid = t2.metaid AND t1.affiliateid = '2';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t6 system PRIMARY NULL NULL NULL 1
1 SIMPLE t1 ref t1_affiliateid,t1_metaid t1_affiliateid 4 const 1
1 SIMPLE t4 ref PRIMARY,t4_formatclassid,t4_formats_idx t4_formats_idx 1 const 1 Using index condition; Using where; Using join buffer (flat, BKA join)
1 SIMPLE t5 eq_ref PRIMARY,t5_formattypeid PRIMARY 4 test.t4.formatclassid 1 Using where; Using join buffer (incremental, BKA join)
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.metaid 1 Using join buffer (incremental, BKA join)
1 SIMPLE t7 ref PRIMARY PRIMARY 4 test.t1.metaid 1 Using index
1 SIMPLE t3 ref t3_metaid,t3_formatid,t3_metaidformatid t3_metaid 4 test.t1.metaid 2 Using where; Using join buffer (flat, BKA join)
1 SIMPLE t8 eq_ref PRIMARY PRIMARY 4 test.t7.artistid 1 Using join buffer (incremental, BKA join)
1 SIMPLE t9 index PRIMARY,t9_subgenreid,t9_metaid PRIMARY 8 NULL 2 Using where; Using index; Using join buffer (incremental, BNL join)
1 SIMPLE t10 eq_ref PRIMARY,t10_genreid PRIMARY 4 test.t9.subgenreid 1 Using join buffer (incremental, BKA join)
1 SIMPLE t11 eq_ref PRIMARY PRIMARY 4 test.t10.genreid 1 Using join buffer (incremental, BKA join)
SELECT t1.uniquekey, t1.xml AS affiliateXml,
t8.name AS artistName, t8.artistid,
t11.name AS genreName, t11.genreid, t11.priority AS genrePriority,
t10.subgenreid, t10.name AS subgenreName,
t2.name AS metaName, t2.metaid, t2.xml AS metaXml,
t4.priority + t5.priority + t6.priority AS overallPriority,
t3.path AS path, t3.mediaid,
t4.formatid, t4.name AS formatName,
t5.formatclassid, t5.name AS formatclassName,
t6.formattypeid, t6.name AS formattypeName
FROM t1, t2, t3, t4, t5, t6, t7, t8, t9, t10, t11
WHERE t7.metaid = t2.metaid AND t7.artistid = t8.artistid AND
t9.metaid = t2.metaid AND t9.subgenreid = t10.subgenreid AND
t10.genreid = t11.genreid AND t3.metaid = t2.metaid AND
t3.formatid = t4.formatid AND t4.formatclassid = t5.formatclassid AND
t4.canaddtocapability = 'Y' AND t5.formattypeid = t6.formattypeid AND
t6.formattypeid IN (2) AND (t3.formatid IN (31, 8, 76)) AND
t1.metaid = t2.metaid AND t1.affiliateid = '2';
uniquekey affiliateXml artistName artistid genreName genreid genrePriority subgenreid subgenreName metaName metaid metaXml overallPriority path mediaid formatid formatName formatclassid formatclassName formattypeid formattypeName
DROP TABLE t1,t2,t3,t4,t5,t6,t7,t8,t9,t10,t11;
CREATE TABLE t1 (a1 int, filler1 char(64) default ' ' );
CREATE TABLE t2 (
a2 int, b2 int, filler2 char(64) default ' ',
PRIMARY KEY idx(a2,b2,filler2)
) ;
CREATE TABLE t3 (b3 int, c3 int, INDEX idx(b3));
INSERT INTO t1(a1) VALUES
(4), (7), (1), (9), (8), (5), (3), (6), (2);
INSERT INTO t2(a2,b2) VALUES
(1,30), (3,40), (2,61), (6,73), (8,92), (9,27), (4,18), (5,84), (7,56),
(4,14), (6,76), (8,98), (7,55), (1,39), (2,68), (3,45), (9,21), (5,81),
(5,88), (2,65), (6,74), (9,23), (1,37), (3,44), (4,17), (8,99), (7,51),
(9,28), (7,52), (1,33), (4,13), (5,87), (3,43), (8,91), (2,62), (6,79),
(3,49), (8,93), (7,34), (5,82), (6,78), (2,63), (1,32), (9,22), (4,11);
INSERT INTO t3 VALUES
(30,302), (92,923), (18,187), (45,459), (30,309),
(39,393), (68,685), (45,458), (21,210), (81,817),
(40,405), (61,618), (73,738), (92,929), (27,275),
(18,188), (84,846), (56,564), (14,144), (76,763),
(98,982), (55,551), (17,174), (99,998), (51,513),
(28,282), (52,527), (33,336), (13,138), (87,878),
(43,431), (91,916), (62,624), (79,797), (49,494),
(93,933), (34,347), (82,829), (78,780), (63,634),
(32,329), (22,228), (11,114), (74,749), (23,236);
set join_cache_level=1;
EXPLAIN
SELECT a1<>a2, a1, a2, b2, b3, c3,
SUBSTR(filler1,1,1) AS s1, SUBSTR(filler2,1,1) AS s2
FROM t1,t2,t3 WHERE a1=a2 AND b2=b3 AND MOD(c3,10)>7;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 9 Using where
1 SIMPLE t2 ref PRIMARY PRIMARY 4 test.t1.a1 1 Using index
1 SIMPLE t3 ref idx idx 5 test.t2.b2 5 Using where
SELECT a1<>a2, a1, a2, b2, b3, c3,
SUBSTR(filler1,1,1) AS s1, SUBSTR(filler2,1,1) AS s2
FROM t1,t2,t3 WHERE a1=a2 AND b2=b3 AND MOD(c3,10)>7;
a1<>a2 a1 a2 b2 b3 c3 s1 s2
0 4 4 13 13 138
0 4 4 18 18 188
0 1 1 30 30 309
0 1 1 32 32 329
0 9 9 22 22 228
0 8 8 92 92 929
0 8 8 99 99 998
0 5 5 82 82 829
0 5 5 87 87 878
0 3 3 45 45 459
0 3 3 45 45 458
0 6 6 73 73 738
0 6 6 74 74 749
0 2 2 61 61 618
set join_cache_level=5;
set join_buffer_size=512;
EXPLAIN
SELECT a1<>a2, a1, a2, b2, b3, c3,
SUBSTR(filler1,1,1) AS s1, SUBSTR(filler2,1,1) AS s2
FROM t1,t2,t3 WHERE a1=a2 AND b2=b3 AND MOD(c3,10)>7;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 9 Using where
1 SIMPLE t2 ref PRIMARY PRIMARY 4 test.t1.a1 1 Using index
1 SIMPLE t3 ref idx idx 5 test.t2.b2 5 Using where; Using join buffer (flat, BKA join)
SELECT a1<>a2, a1, a2, b2, b3, c3,
SUBSTR(filler1,1,1) AS s1, SUBSTR(filler2,1,1) AS s2
FROM t1,t2,t3 WHERE a1=a2 AND b2=b3 AND MOD(c3,10)>7;
a1<>a2 a1 a2 b2 b3 c3 s1 s2
0 4 4 18 18 188
0 4 4 13 13 138
0 1 1 30 30 309
0 1 1 32 32 329
0 9 9 22 22 228
0 8 8 92 92 929
0 8 8 99 99 998
0 5 5 82 82 829
0 3 3 45 45 459
0 3 3 45 45 458
0 5 5 87 87 878
0 2 2 61 61 618
0 6 6 73 73 738
0 6 6 74 74 749
DROP TABLE t1,t2,t3;
CREATE TABLE t1 (a int, b int, INDEX idx(b));
CREATE TABLE t2 (a int, b int, INDEX idx(a));
INSERT INTO t1 VALUES (5,30), (3,20), (7,40), (2,10), (8,30), (1,10), (4,20);
INSERT INTO t2 VALUES (7,10), (1,20), (2,20), (8,20), (8,10), (1,20);
INSERT INTO t2 VALUES (1,10), (4,20), (3,20), (7,20), (7,10), (1,20);
set join_buffer_size=32;
Warnings:
Warning 1292 Truncated incorrect join_buffer_size value: '32'
set join_cache_level=8;
EXPLAIN SELECT * FROM t1,t2 WHERE t1.a=t2.a AND t1.b >= 30;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL idx NULL NULL NULL 7 Using where
1 SIMPLE t2 ref idx idx 5 test.t1.a 2 Using join buffer (flat, BKAH join)
SELECT * FROM t1,t2 WHERE t1.a=t2.a AND t1.b >= 30;
a b a b
7 40 7 10
7 40 7 10
7 40 7 20
8 30 8 10
8 30 8 20
DROP TABLE t1,t2;
#
# Bug #40134: outer join with not exists optimization and join buffer
#
set join_cache_level=default;
set join_buffer_size=default;
CREATE TABLE t1 (a int NOT NULL);
INSERT INTO t1 VALUES (2), (4), (3), (5), (1);
CREATE TABLE t2 (a int NOT NULL, b int NOT NULL, INDEX i_a(a));
INSERT INTO t2 VALUES (4,10), (2,10), (2,30), (2,20), (4,20);
EXPLAIN
SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.a WHERE t2.b IS NULL;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 5
1 SIMPLE t2 ref i_a i_a 4 test.t1.a 2 Using where; Not exists
SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.a WHERE t2.b IS NULL;
a a b
3 NULL NULL
5 NULL NULL
1 NULL NULL
SET join_cache_level=6;
EXPLAIN
SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.a WHERE t2.b IS NULL;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 5
1 SIMPLE t2 ref i_a i_a 4 test.t1.a 2 Using where; Not exists; Using join buffer (flat, BKA join)
SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.a WHERE t2.b IS NULL;
a a b
3 NULL NULL
5 NULL NULL
1 NULL NULL
DROP TABLE t1, t2;
set join_cache_level=default;
set join_buffer_size=default;
#
# BUG#40136: Group by is ignored when join buffer is used for an outer join
#
create table t1(a int PRIMARY KEY, b int);
insert into t1 values
(5, 10), (2, 70), (7, 80), (6, 20), (1, 50), (9, 40), (8, 30), (3, 60);
create table t2 (p int, a int, INDEX i_a(a));
insert into t2 values
(103, 7), (109, 3), (102, 3), (108, 1), (106, 3),
(107, 7), (105, 1), (101, 3), (100, 7), (110, 1);
set @save_join_cache_level=@@join_cache_level;
set join_cache_level=6;
The following must not show "using join cache":
explain
select t1.a, count(t2.p) as count
from t1 left join t2 on t1.a=t2.a and t2.p % 2 = 1 group by t1.a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 8 Using temporary; Using filesort
1 SIMPLE t2 ref i_a i_a 5 test.t1.a 2 Using where; Using join buffer (flat, BKA join)
select t1.a, count(t2.p) as count
from t1 left join t2 on t1.a=t2.a and t2.p % 2 = 1 group by t1.a;
a count
1 1
2 0
3 2
5 0
6 0
7 2
8 0
9 0
set join_cache_level=@save_join_cache_level;
drop table t1, t2;
#
# BUG#40268: Nested outer join with not null-rejecting where condition
# over an inner table which is not the last in the nest
#
CREATE TABLE t2 (a int, b int, c int);
CREATE TABLE t3 (a int, b int, c int);
CREATE TABLE t4 (a int, b int, c int);
INSERT INTO t2 VALUES (3,3,0), (4,2,0), (5,3,0);
INSERT INTO t3 VALUES (1,2,0), (2,2,0);
INSERT INTO t4 VALUES (3,2,0), (4,2,0);
set join_cache_level=6;
SELECT t2.a,t2.b,t3.a,t3.b,t4.a,t4.b
FROM t2 LEFT JOIN (t3, t4) ON t2.b=t4.b
WHERE t3.a+2<t2.a OR t3.c IS NULL;
a b a b a b
4 2 1 2 3 2
4 2 1 2 4 2
3 3 NULL NULL NULL NULL
5 3 NULL NULL NULL NULL
set join_cache_level=default;
DROP TABLE t2, t3, t4;
#
# Bug #40192: outer join with where clause when using BNL
#
create table t1 (a int, b int);
insert into t1 values (2, 20), (3, 30), (1, 10);
create table t2 (a int, c int);
insert into t2 values (1, 101), (3, 102), (1, 100);
set join_cache_level=6;
select * from t1 left join t2 on t1.a=t2.a;
a b a c
1 10 1 101
3 30 3 102
1 10 1 100
2 20 NULL NULL
explain select * from t1 left join t2 on t1.a=t2.a where t2.c=102 or t2.c is null;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
1 SIMPLE t2 ALL NULL NULL NULL NULL 3 Using where; Using join buffer (flat, BNL join)
select * from t1 left join t2 on t1.a=t2.a where t2.c=102 or t2.c is null;
a b a c
3 30 3 102
2 20 NULL NULL
set join_cache_level=default;
drop table t1, t2;
#
# Bug #40317: outer join with with constant on expression equal to FALSE
#
create table t1 (a int);
insert into t1 values (30), (40), (20);
create table t2 (b int);
insert into t2 values (200), (100);
set join_cache_level=6;
select * from t1 left join t2 on (1=0);
a b
30 NULL
40 NULL
20 NULL
explain select * from t1 left join t2 on (1=0) where a=40;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using where
1 SIMPLE t2 ALL NULL NULL NULL NULL 2 Using where; Using join buffer (flat, BNL join)
select * from t1 left join t2 on (1=0) where a=40;
a b
40 NULL
set join_cache_level=0;
explain select * from t1 left join t2 on (1=0);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
1 SIMPLE t2 ALL NULL NULL NULL NULL 2 Using where
set join_cache_level=default;
drop table t1, t2;
#
# Bug #41204: small buffer with big rec_per_key for ref access
#
CREATE TABLE t1 (a int);
INSERT INTO t1 VALUES (0);
INSERT INTO t1(a) SELECT a FROM t1;
INSERT INTO t1(a) SELECT a FROM t1;
INSERT INTO t1(a) SELECT a FROM t1;
INSERT INTO t1(a) SELECT a FROM t1;
INSERT INTO t1(a) SELECT a FROM t1;
INSERT INTO t1(a) SELECT a FROM t1;
INSERT INTO t1(a) SELECT a FROM t1;
INSERT INTO t1(a) SELECT a FROM t1;
INSERT INTO t1(a) SELECT a FROM t1;
INSERT INTO t1(a) SELECT a FROM t1;
INSERT INTO t1(a) SELECT a FROM t1;
INSERT INTO t1 VALUES (20000), (10000);
CREATE TABLE t2 (pk int AUTO_INCREMENT PRIMARY KEY, b int, c int, INDEX idx(b));
INSERT INTO t2(b,c) VALUES (10000, 3), (20000, 7), (20000, 1), (10000, 9), (20000, 5);
INSERT INTO t2(b,c) SELECT b,c FROM t2;
INSERT INTO t2(b,c) SELECT b,c FROM t2;
INSERT INTO t2(b,c) SELECT b,c FROM t2;
INSERT INTO t2(b,c) SELECT b,c FROM t2;
INSERT INTO t2(b,c) SELECT b,c FROM t2;
INSERT INTO t2(b,c) SELECT b,c FROM t2;
INSERT INTO t2(b,c) SELECT b,c FROM t2;
INSERT INTO t2(b,c) SELECT b,c FROM t2;
ANALYZE TABLE t1,t2;
set join_cache_level=6;
set join_buffer_size=1024;
EXPLAIN SELECT AVG(c) FROM t1,t2 WHERE t1.a=t2.b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2050 Using where
1 SIMPLE t2 ref idx idx 5 test.t1.a 640 Using join buffer (flat, BKA join)
SELECT AVG(c) FROM t1,t2 WHERE t1.a=t2.b;
AVG(c)
5.0000
set join_buffer_size=default;
set join_cache_level=default;
DROP TABLE t1, t2;
#
# Bug #41894: big join buffer of level 7 used to join records
# with null values in place of varchar strings
#
CREATE TABLE t1 (a int NOT NULL AUTO_INCREMENT PRIMARY KEY,
b varchar(127) DEFAULT NULL);
INSERT INTO t1(a) VALUES (1);
INSERT INTO t1(b) SELECT b FROM t1;
INSERT INTO t1(b) SELECT b FROM t1;
INSERT INTO t1(b) SELECT b FROM t1;
INSERT INTO t1(b) SELECT b FROM t1;
INSERT INTO t1(b) SELECT b FROM t1;
INSERT INTO t1(b) SELECT b FROM t1;
INSERT INTO t1(b) SELECT b FROM t1;
INSERT INTO t1(b) SELECT b FROM t1;
INSERT INTO t1(b) SELECT b FROM t1;
INSERT INTO t1(b) SELECT b FROM t1;
INSERT INTO t1(b) SELECT b FROM t1;
INSERT INTO t1(b) SELECT b FROM t1;
INSERT INTO t1(b) SELECT b FROM t1;
INSERT INTO t1(b) SELECT b FROM t1;
CREATE TABLE t2 (a int NOT NULL PRIMARY KEY, b varchar(127) DEFAULT NULL);
INSERT INTO t2 SELECT * FROM t1;
CREATE TABLE t3 (a int NOT NULL PRIMARY KEY, b varchar(127) DEFAULT NULL);
INSERT INTO t3 SELECT * FROM t1;
set join_cache_level=7;
set join_buffer_size=1024*1024;
EXPLAIN
SELECT COUNT(*) FROM t1,t2,t3
WHERE t1.a=t2.a AND t2.a=t3.a AND
t1.b IS NULL AND t2.b IS NULL AND t3.b IS NULL;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL PRIMARY NULL NULL NULL 16384 Using where
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.a 1 Using where; Using join buffer (flat, BKAH join)
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.a 1 Using where; Using join buffer (flat, BKAH join)
SELECT COUNT(*) FROM t1,t2,t3
WHERE t1.a=t2.a AND t2.a=t3.a AND
t1.b IS NULL AND t2.b IS NULL AND t3.b IS NULL;
COUNT(*)
16384
set join_buffer_size=default;
set join_cache_level=default;
DROP TABLE t1,t2,t3;
#
# Bug #42020: join buffer is used for outer join with fields of
# several outer tables in join buffer
#
CREATE TABLE t1 (
a bigint NOT NULL,
PRIMARY KEY (a)
);
INSERT INTO t1 VALUES
(2), (1);
CREATE TABLE t2 (
a bigint NOT NULL,
b bigint NOT NULL,
PRIMARY KEY (a,b)
);
INSERT INTO t2 VALUES
(2,30), (2,40), (2,50), (2,60), (2,70), (2,80),
(1,10), (1, 20), (1,30), (1,40), (1,50);
CREATE TABLE t3 (
pk bigint NOT NULL AUTO_INCREMENT,
a bigint NOT NULL,
b bigint NOT NULL,
val bigint DEFAULT '0',
PRIMARY KEY (pk),
KEY idx (a,b)
);
INSERT INTO t3(a,b) VALUES
(2,30), (2,40), (2,50), (2,60), (2,70), (2,80),
(4,30), (4,40), (4,50), (4,60), (4,70), (4,80),
(5,30), (5,40), (5,50), (5,60), (5,70), (5,80),
(7,30), (7,40), (7,50), (7,60), (7,70), (7,80);
set join_cache_level=0;
SELECT t1.a, t2.a, t3.a, t2.b, t3.b, t3.val
FROM (t1,t2) LEFT JOIN t3 ON (t1.a=t3.a AND t2.b=t3.b)
WHERE t1.a=t2.a;
a a a b b val
1 1 NULL 10 NULL NULL
1 1 NULL 20 NULL NULL
1 1 NULL 30 NULL NULL
1 1 NULL 40 NULL NULL
1 1 NULL 50 NULL NULL
2 2 2 30 30 0
2 2 2 40 40 0
2 2 2 50 50 0
2 2 2 60 60 0
2 2 2 70 70 0
2 2 2 80 80 0
set join_cache_level=6;
set join_buffer_size=256;
EXPLAIN
SELECT t1.a, t2.a, t3.a, t2.b, t3.b, t3.val
FROM (t1,t2) LEFT JOIN t3 ON (t1.a=t3.a AND t2.b=t3.b)
WHERE t1.a=t2.a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index PRIMARY PRIMARY 8 NULL 2 Using index
1 SIMPLE t2 ref PRIMARY PRIMARY 8 test.t1.a 1 Using index
1 SIMPLE t3 ref idx idx 16 test.t1.a,test.t2.b 2 Using join buffer (flat, BKA join)
SELECT t1.a, t2.a, t3.a, t2.b, t3.b, t3.val
FROM (t1,t2) LEFT JOIN t3 ON (t1.a=t3.a AND t2.b=t3.b)
WHERE t1.a=t2.a;
a a a b b val
1 1 NULL 10 NULL NULL
1 1 NULL 20 NULL NULL
1 1 NULL 30 NULL NULL
1 1 NULL 40 NULL NULL
1 1 NULL 50 NULL NULL
2 2 2 30 30 0
2 2 2 40 40 0
2 2 2 50 50 0
2 2 2 60 60 0
2 2 2 70 70 0
2 2 2 80 80 0
DROP INDEX idx ON t3;
set join_cache_level=2;
EXPLAIN
SELECT t1.a, t2.a, t3.a, t2.b, t3.b, t3.val
FROM (t1,t2) LEFT JOIN t3 ON (t1.a=t3.a AND t2.b=t3.b)
WHERE t1.a=t2.a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index PRIMARY PRIMARY 8 NULL 2 Using index
1 SIMPLE t2 ref PRIMARY PRIMARY 8 test.t1.a 1 Using index
1 SIMPLE t3 ALL NULL NULL NULL NULL 24 Using where; Using join buffer (flat, BNL join)
SELECT t1.a, t2.a, t3.a, t2.b, t3.b, t3.val
FROM (t1,t2) LEFT JOIN t3 ON (t1.a=t3.a AND t2.b=t3.b)
WHERE t1.a=t2.a;
a a a b b val
1 1 NULL 10 NULL NULL
1 1 NULL 20 NULL NULL
1 1 NULL 30 NULL NULL
1 1 NULL 40 NULL NULL
1 1 NULL 50 NULL NULL
2 2 2 30 30 0
2 2 2 40 40 0
2 2 2 50 50 0
2 2 2 60 60 0
2 2 2 70 70 0
2 2 2 80 80 0
set join_buffer_size=default;
set join_cache_level=default;
DROP TABLE t1,t2,t3;
create table t1(f1 int, f2 int);
insert into t1 values (1,1),(2,2),(3,3);
create table t2(f1 int not null, f2 int not null, f3 char(200), key(f1,f2));
insert into t2 values (1,1, 'qwerty'),(1,2, 'qwerty'),(1,3, 'qwerty');
insert into t2 values (2,1, 'qwerty'),(2,2, 'qwerty'),(2,3, 'qwerty'),
(2,4, 'qwerty'),(2,5, 'qwerty');
insert into t2 values (3,1, 'qwerty'),(3,4, 'qwerty');
insert into t2 values (4,1, 'qwerty'),(4,2, 'qwerty'),(4,3, 'qwerty'),
(4,4, 'qwerty');
insert into t2 values (1,1, 'qwerty'),(1,2, 'qwerty'),(1,3, 'qwerty');
insert into t2 values (2,1, 'qwerty'),(2,2, 'qwerty'),(2,3, 'qwerty'),
(2,4, 'qwerty'),(2,5, 'qwerty');
insert into t2 values (3,1, 'qwerty'),(3,4, 'qwerty');
insert into t2 values (4,1, 'qwerty'),(4,2, 'qwerty'),(4,3, 'qwerty'),
(4,4, 'qwerty');
set join_cache_level=5;
select t2.f1, t2.f2, t2.f3 from t1,t2
where t1.f1=t2.f1 and t2.f2 between t1.f1 and t1.f2 and t2.f2 + 1 >= t1.f1 + 1;
f1 f2 f3
1 1 qwerty
2 2 qwerty
1 1 qwerty
2 2 qwerty
explain select t2.f1, t2.f2, t2.f3 from t1,t2
where t1.f1=t2.f1 and t2.f2 between t1.f1 and t2.f2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using where
1 SIMPLE t2 ref f1 f1 4 test.t1.f1 3 Using index condition(BKA); Using join buffer (flat, BKA join)
set join_cache_level=6;
select t2.f1, t2.f2, t2.f3 from t1,t2
where t1.f1=t2.f1 and t2.f2 between t1.f1 and t1.f2 and t2.f2 + 1 >= t1.f1 + 1;
f1 f2 f3
1 1 qwerty
2 2 qwerty
1 1 qwerty
2 2 qwerty
explain select t2.f1, t2.f2, t2.f3 from t1,t2
where t1.f1=t2.f1 and t2.f2 between t1.f1 and t2.f2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using where
1 SIMPLE t2 ref f1 f1 4 test.t1.f1 3 Using index condition(BKA); Using join buffer (flat, BKA join)
set join_cache_level=7;
select t2.f1, t2.f2, t2.f3 from t1,t2
where t1.f1=t2.f1 and t2.f2 between t1.f1 and t1.f2 and t2.f2 + 1 >= t1.f1 + 1;
f1 f2 f3
1 1 qwerty
2 2 qwerty
1 1 qwerty
2 2 qwerty
explain select t2.f1, t2.f2, t2.f3 from t1,t2
where t1.f1=t2.f1 and t2.f2 between t1.f1 and t2.f2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using where
1 SIMPLE t2 ref f1 f1 4 test.t1.f1 3 Using index condition(BKA); Using where; Using join buffer (flat, BKAH join)
set join_cache_level=8;
select t2.f1, t2.f2, t2.f3 from t1,t2
where t1.f1=t2.f1 and t2.f2 between t1.f1 and t1.f2 and t2.f2 + 1 >= t1.f1 + 1;
f1 f2 f3
1 1 qwerty
2 2 qwerty
1 1 qwerty
2 2 qwerty
explain select t2.f1, t2.f2, t2.f3 from t1,t2
where t1.f1=t2.f1 and t2.f2 between t1.f1 and t2.f2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using where
1 SIMPLE t2 ref f1 f1 4 test.t1.f1 3 Using index condition(BKA); Using where; Using join buffer (flat, BKAH join)
drop table t1,t2;
set join_cache_level=default;
#
# Bug #42955: join with GROUP BY/ORDER BY and when BKA is enabled
#
create table t1 (d int, id1 int, index idx1 (d, id1));
insert into t1 values
(3, 20), (2, 40), (3, 10), (1, 10), (3, 20), (1, 40), (2, 30), (3, 30);
create table t2 (id1 int, id2 int, index idx2 (id1));
insert into t2 values
(20, 100), (30, 400), (20, 400), (30, 200), (10, 300), (10, 200), (40, 100),
(40, 200), (30, 300), (10, 400), (20, 200), (20, 300);
set join_cache_level=6;
explain
select t1.id1, sum(t2.id2) from t1 join t2 on t1.id1=t2.id1
where t1.d=3 group by t1.id1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref idx1 idx1 5 const 4 Using where; Using index; Using temporary; Using filesort
1 SIMPLE t2 ref idx2 idx2 5 test.t1.id1 2 Using join buffer (flat, BKA join)
select t1.id1, sum(t2.id2) from t1 join t2 on t1.id1=t2.id1
where t1.d=3 group by t1.id1;
id1 sum(t2.id2)
10 900
20 2000
30 900
explain
select t1.id1 from t1 join t2 on t1.id1=t2.id1
where t1.d=3 and t2.id2 > 200 order by t1.id1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ref idx1 idx1 5 const 4 Using where; Using index; Using temporary; Using filesort
1 SIMPLE t2 ref idx2 idx2 5 test.t1.id1 2 Using where; Using join buffer (flat, BKA join)
select t1.id1 from t1 join t2 on t1.id1=t2.id1
where t1.d=3 and t2.id2 > 200 order by t1.id1;
id1
10
10
20
20
20
20
30
30
set join_cache_level=default;
drop table t1,t2;
#
# Bug #44019: star-like multi-join query executed join_cache_level=6
#
create table t1 (a int, b int, c int, d int);
create table t2 (b int, e varchar(16), index idx(b));
create table t3 (d int, f varchar(16), index idx(d));
create table t4 (c int, g varchar(16), index idx(c));
insert into t1 values
(5, 50, 500, 5000), (3, 30, 300, 3000), (9, 90, 900, 9000),
(2, 20, 200, 2000), (4, 40, 400, 4000), (8, 80, 800, 800),
(7, 70, 700, 7000);
insert into t2 values
(30, 'bbb'), (10, 'b'), (70, 'bbbbbbb'), (60, 'bbbbbb'),
(31, 'bbb'), (11, 'b'), (71, 'bbbbbbb'), (61, 'bbbbbb'),
(32, 'bbb'), (12, 'b'), (72, 'bbbbbbb'), (62, 'bbbbbb');
insert into t3 values
(4000, 'dddd'), (3000, 'ddd'), (1000, 'd'), (8000, 'dddddddd'),
(4001, 'dddd'), (3001, 'ddd'), (1001, 'd'), (8001, 'dddddddd'),
(4002, 'dddd'), (3002, 'ddd'), (1002, 'd'), (8002, 'dddddddd');
insert into t4 values
(200, 'cc'), (600, 'cccccc'), (300, 'ccc'), (500, 'ccccc'),
(201, 'cc'), (601, 'cccccc'), (301, 'ccc'), (501, 'ccccc'),
(202, 'cc'), (602, 'cccccc'), (302, 'ccc'), (502, 'ccccc');
analyze table t2,t3,t4;
set join_cache_level=1;
explain
select t1.a, t1.b, t1.c, t1.d, t2.e, t3.f, t4.g from t1,t2,t3,t4
where t2.b=t1.b and t3.d=t1.d and t4.c=t1.c;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 7 Using where
1 SIMPLE t2 ref idx idx 5 test.t1.b 1
1 SIMPLE t3 ref idx idx 5 test.t1.d 1
1 SIMPLE t4 ref idx idx 5 test.t1.c 1
select t1.a, t1.b, t1.c, t1.d, t2.e, t3.f, t4.g from t1,t2,t3,t4
where t2.b=t1.b and t3.d=t1.d and t4.c=t1.c;
a b c d e f g
3 30 300 3000 bbb ddd ccc
set join_cache_level=6;
explain
select t1.a, t1.b, t1.c, t1.d, t2.e, t3.f, t4.g from t1,t2,t3,t4
where t2.b=t1.b and t3.d=t1.d and t4.c=t1.c;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 7 Using where
1 SIMPLE t2 ref idx idx 5 test.t1.b 1 Using join buffer (flat, BKA join)
1 SIMPLE t3 ref idx idx 5 test.t1.d 1 Using join buffer (incremental, BKA join)
1 SIMPLE t4 ref idx idx 5 test.t1.c 1 Using join buffer (incremental, BKA join)
select t1.a, t1.b, t1.c, t1.d, t2.e, t3.f, t4.g from t1,t2,t3,t4
where t2.b=t1.b and t3.d=t1.d and t4.c=t1.c;
a b c d e f g
3 30 300 3000 bbb ddd ccc
set join_cache_level=default;
drop table t1,t2,t3,t4;
#
# Bug #44250: Corruption of linked join buffers when using BKA
#
CREATE TABLE t1 (
id1 bigint(20) DEFAULT NULL,
id2 bigint(20) DEFAULT NULL,
id3 bigint(20) DEFAULT NULL,
num1 bigint(20) DEFAULT NULL,
num2 int(11) DEFAULT NULL,
num3 bigint(20) DEFAULT NULL
);
CREATE TABLE t2 (
id3 bigint(20) NOT NULL DEFAULT '0',
id4 bigint(20) DEFAULT NULL,
enum1 enum('Enabled','Disabled','Paused') DEFAULT NULL,
PRIMARY KEY (id3)
);
CREATE TABLE t3 (
id4 bigint(20) NOT NULL DEFAULT '0',
text1 text,
PRIMARY KEY (id4)
);
CREATE TABLE t4 (
id2 bigint(20) NOT NULL DEFAULT '0',
dummy int(11) DEFAULT '0',
PRIMARY KEY (id2)
);
CREATE TABLE t5 (
id1 bigint(20) NOT NULL DEFAULT '0',
id2 bigint(20) NOT NULL DEFAULT '0',
enum2 enum('Active','Deleted','Paused') DEFAULT NULL,
PRIMARY KEY (id1,id2)
);
set join_cache_level=8;
set join_buffer_size=2048;
EXPLAIN
SELECT STRAIGHT_JOIN t1.id1, t1.num3, t3.text1, t3.id4, t2.id3, t4.dummy
FROM t1 JOIN t2 JOIN t3 JOIN t4 JOIN t5
WHERE t1.id1=t5.id1 AND t1.id2=t5.id2 and t4.id2=t1.id2 AND
t5.enum2='Active' AND t3.id4=t2.id4 AND t2.id3=t1.id3 AND t3.text1<'D';
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 349 Using where
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 8 test.t1.id3 1 Using where; Using join buffer (flat, BKAH join)
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 8 test.t2.id4 1 Using where; Using join buffer (incremental, BKAH join)
1 SIMPLE t4 eq_ref PRIMARY PRIMARY 8 test.t1.id2 1 Using join buffer (incremental, BKAH join)
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 16 test.t1.id1,test.t1.id2 1 Using where; Using join buffer (incremental, BKAH join)
SELECT STRAIGHT_JOIN t1.id1, t1.num3, t3.text1, t3.id4, t2.id3, t4.dummy
FROM t1 JOIN t2 JOIN t3 JOIN t4 JOIN t5
WHERE t1.id1=t5.id1 AND t1.id2=t5.id2 and t4.id2=t1.id2 AND
t5.enum2='Active' AND t3.id4=t2.id4 AND t2.id3=t1.id3 AND t3.text1<'D';
id1 num3 text1 id4 id3 dummy
228172702 14 AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA 2567095402 2667134182 0
228172702 134 AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA 2567095402 2667134182 0
228172702 15 AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA 2567095402 2667134182 0
228172702 3 AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA 2567095402 2667134182 0
228808822 61 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0
228808822 13 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0
228808822 60 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0
228808822 13 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0
228808822 3 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0
228808822 4 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0
228808822 6 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0
228808822 18 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0
228808822 1 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0
228808822 3 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0
228808822 17 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0
228808822 50 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0
228808822 4 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0
228808822 89 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0
228808822 19 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0
228808822 9 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0
228808822 84 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0
228808822 14 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0
228808822 1 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0
228808822 10 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0
228808822 26 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0
228808822 4 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0
228808822 3 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0
228808822 1 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0
228808822 3 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0
228808822 28 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0
228808822 62 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0
set join_buffer_size=default;
set join_cache_level=default;
DROP TABLE t1,t2,t3,t4,t5;
#
# Bug#45267: Incomplete check caused wrong result.
#
CREATE TABLE t1 (
`pk` int(11) NOT NULL AUTO_INCREMENT PRIMARY KEY
);
CREATE TABLE t3 (
`pk` int(11) NOT NULL AUTO_INCREMENT PRIMARY KEY
);
INSERT INTO t3 VALUES
(1),(2),(3),(4),(5),(6),(7),(8),(9),(10),(11),(12),(13),(14),(15),
(16),(17),(18),(19),(20);
CREATE TABLE t2 (
`pk` int(11) NOT NULL AUTO_INCREMENT,
`int_nokey` int(11) NOT NULL,
`time_key` time NOT NULL,
PRIMARY KEY (`pk`),
KEY `time_key` (`time_key`)
);
INSERT INTO t2 VALUES (10,9,'22:36:46'),(11,0,'08:46:46');
SELECT DISTINCT t1.`pk`
FROM t1 RIGHT JOIN t2 STRAIGHT_JOIN t3 ON t2.`int_nokey` ON t2.`time_key`
GROUP BY 1;
pk
NULL
DROP TABLE IF EXISTS t1, t2, t3;
#
# Bug #46328: Use of aggregate function without GROUP BY clause
# returns many rows (vs. one )
#
CREATE TABLE t1 (
int_key int(11) NOT NULL,
KEY int_key (int_key)
);
INSERT INTO t1 VALUES
(0),(2),(2),(2),(3),(4),(5),(5),(6),(6),(8),(8),(9),(9);
CREATE TABLE t2 (
int_key int(11) NOT NULL,
KEY int_key (int_key)
);
INSERT INTO t2 VALUES (2),(3);
# The query shall return 1 record with a max value 9 and one of the
# int_key values inserted above (undefined which one). A changed
# execution plan may change the value in the second column
SELECT MAX(t1.int_key), t1.int_key
FROM t1 STRAIGHT_JOIN t2
ORDER BY t1.int_key;
MAX(t1.int_key) int_key
9 0
explain
SELECT MAX(t1.int_key), t1.int_key
FROM t1 STRAIGHT_JOIN t2
ORDER BY t1.int_key;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index NULL int_key 4 NULL 14 Using index
1 SIMPLE t2 index NULL int_key 4 NULL 2 Using index; Using join buffer (flat, BNL join)
DROP TABLE t1,t2;
SET join_cache_level=default;
#
# Regression test for
# Bug#46733 - NULL value not returned for aggregate on empty result
# set w/ semijoin on
#
CREATE TABLE t1 (
i int(11) NOT NULL,
v varchar(1) DEFAULT NULL,
PRIMARY KEY (i)
);
INSERT INTO t1 VALUES (10,'a'),(11,'b'),(12,'c'),(13,'d');
CREATE TABLE t2 (
i int(11) NOT NULL,
v varchar(1) DEFAULT NULL,
PRIMARY KEY (i)
);
INSERT INTO t2 VALUES (1,'x'),(2,'y');
SELECT MAX(t1.i)
FROM t1 JOIN t2 ON t2.v
ORDER BY t2.v;
MAX(t1.i)
NULL
EXPLAIN
SELECT MAX(t1.i)
FROM t1 JOIN t2 ON t2.v
ORDER BY t2.v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ALL NULL NULL NULL NULL 2 Using where
1 SIMPLE t1 index NULL PRIMARY 4 NULL 4 Using index; Using join buffer (flat, BNL join)
DROP TABLE t1,t2;
#
# Bug #45092: join buffer contains two blob columns one of which is
# used in the key employed to access the joined table
#
CREATE TABLE t1 (c1 int, c2 int, key (c2));
INSERT INTO t1 VALUES (1,1);
INSERT INTO t1 VALUES (2,2);
CREATE TABLE t2 (c1 text, c2 text);
INSERT INTO t2 VALUES('tt', 'uu');
INSERT INTO t2 VALUES('zzzz', 'xxxxxxxxx');
ANALYZE TABLE t1,t2;
set join_cache_level=6;
SELECT t1.*, t2.*, LENGTH(t2.c1), LENGTH(t2.c2) FROM t1,t2
WHERE t1.c2=LENGTH(t2.c2) and t1.c1=LENGTH(t2.c1);
c1 c2 c1 c2 LENGTH(t2.c1) LENGTH(t2.c2)
2 2 tt uu 2 2
set join_cache_level=default;
DROP TABLE t1,t2;
#
# Bug #51092: linked join buffer is used for a 3-way cross join query
# that selects only records of the first table
#
create table t1 (a int, b int);
insert into t1 values (1,1),(2,2);
create table t2 (a int, b int);
insert into t2 values (1,1),(2,2);
create table t3 (a int, b int);
insert into t3 values (1,1),(2,2);
explain select t1.* from t1,t2,t3;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
1 SIMPLE t2 ALL NULL NULL NULL NULL 2 Using join buffer (flat, BNL join)
1 SIMPLE t3 ALL NULL NULL NULL NULL 2 Using join buffer (flat, BNL join)
select t1.* from t1,t2,t3;
a b
1 1
2 2
1 1
2 2
1 1
2 2
1 1
2 2
set join_cache_level=2;
explain select t1.* from t1,t2,t3;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
1 SIMPLE t2 ALL NULL NULL NULL NULL 2 Using join buffer (flat, BNL join)
1 SIMPLE t3 ALL NULL NULL NULL NULL 2 Using join buffer (incremental, BNL join)
select t1.* from t1,t2,t3;
a b
1 1
2 2
1 1
2 2
1 1
2 2
1 1
2 2
set join_cache_level=default;
drop table t1,t2,t3;
#
# Bug #52394: using join buffer for 3 table join with ref access
# LP #623209: and no references to the columns of the middle table
#
set join_cache_level=6;
CREATE TABLE t1 (a int(11), b varchar(1));
INSERT INTO t1 VALUES (6,'r'),(27,'o');
CREATE TABLE t2(a int);
INSERT INTO t2 VALUES(1),(2),(3),(4),(5);
CREATE TABLE t3 (a int(11) primary key, b varchar(1));
INSERT INTO t3 VALUES
(14,'d'),(15,'z'),(16,'e'),(17,'h'),(18,'b'),(19,'s'),(20,'e'),
(21,'j'),(22,'e'),(23,'f'),(24,'v'),(25,'x'),(26,'m'),(27,'o');
EXPLAIN
SELECT t3.a FROM t1,t2,t3 WHERE t1.a = t3.a AND t1.b = t3.b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2 Using where
1 SIMPLE t2 ALL NULL NULL NULL NULL 5 Using join buffer (flat, BNL join)
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.a 1 Using where; Using join buffer (incremental, BKA join)
SELECT t3.a FROM t1,t2,t3 WHERE t1.a = t3.a AND t1.b = t3.b;
a
27
27
27
27
27
DROP TABLE t1,t2,t3;
set join_cache_level=default;
#
# Bug #51084: Batched key access crashes for SELECT with
# derived table and LEFT JOIN
#
CREATE TABLE t1 (
carrier int,
id int PRIMARY KEY
);
INSERT INTO t1 VALUES (1,11),(1,12),(2,13);
CREATE TABLE t2 (
scan_date int,
package_id int
);
INSERT INTO t2 VALUES (2008,21),(2008,22);
CREATE TABLE t3 (
carrier int PRIMARY KEY,
id int
);
INSERT INTO t3 VALUES (1,31);
CREATE TABLE t4 (
carrier_id int,
INDEX carrier_id(carrier_id)
);
INSERT INTO t4 VALUES (31),(32);
SET join_cache_level=8;
SELECT COUNT(*)
FROM (t2 JOIN t1) LEFT JOIN (t3 JOIN t4 ON t3.id = t4.carrier_id)
ON t3.carrier = t1.carrier;
COUNT(*)
6
EXPLAIN
SELECT COUNT(*)
FROM (t2 JOIN t1) LEFT JOIN (t3 JOIN t4 ON t3.id = t4.carrier_id)
ON t3.carrier = t1.carrier;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ALL NULL NULL NULL NULL 2
1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using join buffer (flat, BNL join)
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t1.carrier 1 Using where
1 SIMPLE t4 ref carrier_id carrier_id 5 test.t3.id 2 Using index
SET join_cache_level=default;
DROP TABLE t1,t2,t3,t4;
#
# Bug #52636: allowing JOINs on NULL values w/ join_cache_level = 5-8
#
CREATE TABLE t1 (b int);
INSERT INTO t1 VALUES (NULL),(3);
CREATE TABLE t2 (a int, b int, KEY (b));
INSERT INTO t2 VALUES (100,NULL),(150,200);
set join_cache_level = 5;
explain SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
1 SIMPLE t2 ref b b 5 test.t1.b 2 Using where; Using join buffer (flat, BKA join)
SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
a
NULL
NULL
set join_cache_level = 8;
explain SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
1 SIMPLE t2 ref b b 5 test.t1.b 2 Using where; Using join buffer (flat, BKAH join)
SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
a
NULL
NULL
delete from t1;
INSERT INTO t1 VALUES (NULL),(NULL);
set join_cache_level = 5;
explain SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
1 SIMPLE t2 ref b b 5 test.t1.b 2 Using where; Using join buffer (flat, BKA join)
SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
a
NULL
NULL
DROP TABLE t1,t2;
CREATE TABLE t1 (b varchar(100));
INSERT INTO t1 VALUES (NULL),("some varchar");
CREATE TABLE t2 (a int, b varchar(100), KEY (b));
INSERT INTO t2 VALUES (100,NULL),(150,"varchar"),(200,NULL),(250,"long long varchar");
set join_cache_level = 5;
explain SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
1 SIMPLE t2 ref b b 103 test.t1.b 2 Using where; Using join buffer (flat, BKA join)
SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
a
NULL
NULL
set join_cache_level = 8;
explain SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
1 SIMPLE t2 ref b b 103 test.t1.b 2 Using where; Using join buffer (flat, BKAH join)
SELECT t2.a FROM t1 LEFT JOIN t2 ON t2.b = t1.b;
a
NULL
NULL
set join_cache_level = default;
DROP TABLE t1,t2;
#
# Bug #54359: Extra rows with join_cache_level=7,8 and two joins
# and multi-column index"
#
CREATE TABLE t1 (
pk int NOT NULL,
a int DEFAULT NULL,
b varchar(16) DEFAULT NULL,
c varchar(16) DEFAULT NULL,
INDEX idx (b,a))
;
INSERT INTO t1 VALUES (4,9,'k','k');
INSERT INTO t1 VALUES (12,5,'k','k');
set join_cache_level = 8;
EXPLAIN
SELECT t.a FROM t1 t, t1 s FORCE INDEX(idx)
WHERE s.pk AND s.a >= t.pk AND s.b = t.c;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t ALL NULL NULL NULL NULL 2 Using where
1 SIMPLE s ref idx idx 19 test.t.c 1 Using index condition(BKA); Using where; Using join buffer (flat, BKAH join)
SELECT t.a FROM t1 t, t1 s FORCE INDEX(idx)
WHERE s.pk AND s.a >= t.pk AND s.b = t.c;
a
9
9
set join_cache_level = default;
DROP TABLE t1;
#
# Bug #54235: Extra rows with join_cache_level=6,8 and two LEFT JOINs
#
CREATE TABLE t1 (a int);
CREATE TABLE t2 (a int);
CREATE TABLE t3 (a int);
CREATE TABLE t4 (a int);
INSERT INTO t1 VALUES (null), (2), (null), (1);
set join_cache_level = 6;
EXPLAIN
SELECT t1.a
FROM t1 LEFT JOIN (t2 LEFT JOIN t3 ON t2.a) ON 0
WHERE t1.a OR t3.a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
1 SIMPLE t2 ALL NULL NULL NULL NULL 0 Using where; Using join buffer (flat, BNL join)
1 SIMPLE t3 ALL NULL NULL NULL NULL 0 Using where; Using join buffer (incremental, BNL join)
SELECT t1.a
FROM t1 LEFT JOIN (t2 LEFT JOIN t3 ON t2.a) ON 0
WHERE t1.a OR t3.a;
a
2
1
EXPLAIN
SELECT t1.a
FROM t1 LEFT JOIN (t2 LEFT JOIN (t3 LEFT JOIN t4 ON 1) ON t2.a) ON 0
WHERE t1.a OR t4.a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
1 SIMPLE t2 ALL NULL NULL NULL NULL 0 Using where; Using join buffer (flat, BNL join)
1 SIMPLE t3 ALL NULL NULL NULL NULL 0 Using where; Using join buffer (incremental, BNL join)
1 SIMPLE t4 ALL NULL NULL NULL NULL 0 Using where; Using join buffer (incremental, BNL join)
SELECT t1.a
FROM t1 LEFT JOIN (t2 LEFT JOIN (t3 LEFT JOIN t4 ON 1) ON t2.a) ON 0
WHERE t1.a OR t4.a;
a
2
1
set join_cache_level = default;
DROP TABLE t1,t2,t3,t4;
#
# Bug #663840: Memory overwrite causing crash with hash join
#
SET SESSION join_cache_level=3;
SET SESSION join_buffer_size=100;
Warnings:
Warning 1292 Truncated incorrect join_buffer_size value: '100'
CREATE TABLE t3 (
i int NOT NULL,
j int NOT NULL,
d date NOT NULL,
t time NOT NULL,
v varchar(1) NOT NULL,
u varchar(1) NOT NULL,
INDEX idx (v)
) COLLATE=latin1_bin;
INSERT INTO t3 VALUES
(3,8,'2008-12-04','00:00:00','v','v'), (3,8,'2009-03-28','00:00:00','f','f'),
(3,5,'1900-01-01','00:55:47','v','v'), (2,8,'2009-10-02','00:00:00','s','s'),
(1,8,'1900-01-01','20:51:59','a','a'), (0,6,'2008-06-04','09:47:27','p','p'),
(8,7,'2009-01-13','21:58:29','z','z'), (5,2,'1900-01-01','22:45:53','a','a'),
(9,5,'2008-01-28','14:06:48','h','h'), (5,7,'2004-09-18','22:17:16','h','h'),
(4,2,'2006-10-14','14:59:37','v','v'), (2,9,'1900-01-01','23:37:40','v','v'),
(33,142,'2000-11-28','14:14:01','b','b'), (5,3,'2008-04-04','02:54:19','y','y'),
(1,0,'2002-07-13','06:34:26','v','v'), (9,3,'2003-01-03','18:07:38','m','m'),
(1,5,'2006-04-02','13:55:23','z','z'), (3,9,'2006-10-19','20:32:28','n','n'),
(8,1,'2005-06-08','11:57:44','d','d'), (231,107,'2006-12-26','03:10:35','a','a');
CREATE TABLE t1 SELECT * FROM t3;
DELETE FROM t1 WHERE i > 8;
CREATE TABLE t2 SELECT * FROM t3;
DELETE FROM t2 WHERE j > 10;
EXPLAIN
SELECT t1.i, t1.d, t1.v, t2.i, t2.d, t2.t, t2.v FROM t1,t2,t3
WHERE t3.u <='a' AND t2.j < 5 AND t3.v = t2.u;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 16
1 SIMPLE t2 ALL NULL NULL NULL NULL 18 Using where; Using join buffer (flat, BNL join)
1 SIMPLE t3 ref idx idx 3 test.t2.u 2 Using where
SELECT t1.i, t1.d, t1.v, t2.i, t2.d, t2.t, t2.v FROM t1,t2,t3
WHERE t3.u <='a' AND t2.j < 5 AND t3.v = t2.u;
i d v i d t v
0 2008-06-04 p 5 1900-01-01 22:45:53 a
0 2008-06-04 p 5 1900-01-01 22:45:53 a
0 2008-06-04 p 5 1900-01-01 22:45:53 a
1 1900-01-01 a 5 1900-01-01 22:45:53 a
1 1900-01-01 a 5 1900-01-01 22:45:53 a
1 1900-01-01 a 5 1900-01-01 22:45:53 a
1 2002-07-13 v 5 1900-01-01 22:45:53 a
1 2002-07-13 v 5 1900-01-01 22:45:53 a
1 2002-07-13 v 5 1900-01-01 22:45:53 a
1 2006-04-02 z 5 1900-01-01 22:45:53 a
1 2006-04-02 z 5 1900-01-01 22:45:53 a
1 2006-04-02 z 5 1900-01-01 22:45:53 a
2 1900-01-01 v 5 1900-01-01 22:45:53 a
2 1900-01-01 v 5 1900-01-01 22:45:53 a
2 1900-01-01 v 5 1900-01-01 22:45:53 a
2 2009-10-02 s 5 1900-01-01 22:45:53 a
2 2009-10-02 s 5 1900-01-01 22:45:53 a
2 2009-10-02 s 5 1900-01-01 22:45:53 a
3 1900-01-01 v 5 1900-01-01 22:45:53 a
3 1900-01-01 v 5 1900-01-01 22:45:53 a
3 1900-01-01 v 5 1900-01-01 22:45:53 a
3 2006-10-19 n 5 1900-01-01 22:45:53 a
3 2006-10-19 n 5 1900-01-01 22:45:53 a
3 2006-10-19 n 5 1900-01-01 22:45:53 a
3 2008-12-04 v 5 1900-01-01 22:45:53 a
3 2008-12-04 v 5 1900-01-01 22:45:53 a
3 2008-12-04 v 5 1900-01-01 22:45:53 a
3 2009-03-28 f 5 1900-01-01 22:45:53 a
3 2009-03-28 f 5 1900-01-01 22:45:53 a
3 2009-03-28 f 5 1900-01-01 22:45:53 a
4 2006-10-14 v 5 1900-01-01 22:45:53 a
4 2006-10-14 v 5 1900-01-01 22:45:53 a
4 2006-10-14 v 5 1900-01-01 22:45:53 a
5 1900-01-01 a 5 1900-01-01 22:45:53 a
5 1900-01-01 a 5 1900-01-01 22:45:53 a
5 1900-01-01 a 5 1900-01-01 22:45:53 a
5 2004-09-18 h 5 1900-01-01 22:45:53 a
5 2004-09-18 h 5 1900-01-01 22:45:53 a
5 2004-09-18 h 5 1900-01-01 22:45:53 a
5 2008-04-04 y 5 1900-01-01 22:45:53 a
5 2008-04-04 y 5 1900-01-01 22:45:53 a
5 2008-04-04 y 5 1900-01-01 22:45:53 a
8 2005-06-08 d 5 1900-01-01 22:45:53 a
8 2005-06-08 d 5 1900-01-01 22:45:53 a
8 2005-06-08 d 5 1900-01-01 22:45:53 a
8 2009-01-13 z 5 1900-01-01 22:45:53 a
8 2009-01-13 z 5 1900-01-01 22:45:53 a
8 2009-01-13 z 5 1900-01-01 22:45:53 a
DROP TABLE t1,t2,t3;
SET SESSION join_cache_level=DEFAULT;
SET SESSION join_buffer_size=DEFAULT;
#
# Bug #664508: 'Simple' GROUP BY + ORDER BY
# when join buffers are used
#
CREATE TABLE t1 (
pk int NOT NULL, i int NOT NULL, v varchar(1) NOT NULL,
PRIMARY KEY (pk), INDEX idx1(i), INDEX idx2 (v,i)
) COLLATE latin1_bin;
INSERT INTO t1 VALUES
(10,8,'v'), (11,8,'f'), (12,5,'v'), (13,8,'s'), (14,8,'a'),
(15,6,'p'), (16,7,'z'), (17,2,'a'), (18,5,'h'), (19,7,'h'),
(25,3,'m'), (26,5,'z'), (27,9,'n'), (28,1,'d'), (29,107,'a');
CREATE TABLE t2 (
pk int NOT NULL, i int NOT NULL, v varchar(1) NOT NULL,
PRIMARY KEY (pk), INDEX idx1(i), INDEX idx2(v,i)
) COLLATE latin1_bin;
INSERT INTO t2 VALUES
(10,8,'v'), (11,8,'f'), (12,5,'v'), (13,8,'s'), (14,8,'a'),
(15,6,'p'), (16,7,'z'), (17,2,'a'), (18,5,'h'), (19,7,'h'),
(20,2,'v'), (21,9,'v'), (22,142,'b'), (23,3,'y'), (24,0,'v'),
(25,3,'m'), (26,5,'z'), (27,9,'n'), (28,1,'d'), (29,107,'a');
CREATE TABLE t3 (
pk int NOT NULL, i int NOT NULL, v varchar(1) NOT NULL,
PRIMARY KEY (pk), INDEX idx1(i), INDEX idx2(v,i)
) COLLATE latin1_bin;
INSERT INTO t3 VALUES
(1,9,'x'), (2,5,'g'), (3,1,'o'), (4,0,'g'), (5,1,'v'),
(6,190,'m'), (7,6,'x'), (8,3,'c'), (9,4,'z'), (10,3,'i'),
(11,186,'x'), (12,1,'g'), (13,8,'q'), (14,226,'m'), (15,133,'p'),
(16,6,'e'), (17,3,'t'), (18,8,'j'), (19,5,'h'), (20,7,'w');
SET SESSION join_cache_level=1;
EXPLAIN
SELECT t2.v FROM t1, t2, t3 WHERE t3.v <> t2.v AND t3.pk = t2.i AND t1.v = t3.v
GROUP BY t2.v ORDER BY t1.pk,t2.v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 index idx1 idx2 7 NULL 20 Using index; Using temporary; Using filesort
1 SIMPLE t3 eq_ref PRIMARY,idx2 PRIMARY 4 test.t2.i 1 Using where
1 SIMPLE t1 ref idx2 idx2 3 test.t3.v 2
SELECT t2.v FROM t1, t2, t3 WHERE t3.v <> t2.v AND t3.pk = t2.i AND t1.v = t3.v
GROUP BY t2.v ORDER BY t1.pk,t2.v;
v
h
z
p
n
v
SET SESSION join_cache_level=6;
EXPLAIN
SELECT t2.v FROM t1, t2, t3 WHERE t3.v <> t2.v AND t3.pk = t2.i AND t1.v = t3.v
GROUP BY t2.v ORDER BY t1.pk,t2.v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ALL idx1 NULL NULL NULL 20 Using temporary; Using filesort
1 SIMPLE t3 eq_ref PRIMARY,idx2 PRIMARY 4 test.t2.i 1 Using where; Using join buffer (flat, BKA join)
1 SIMPLE t1 ref idx2 idx2 3 test.t3.v 2 Using join buffer (incremental, BKA join)
SELECT t2.v FROM t1, t2, t3 WHERE t3.v <> t2.v AND t3.pk = t2.i AND t1.v = t3.v
GROUP BY t2.v ORDER BY t1.pk,t2.v;
v
h
z
n
v
p
SET SESSION join_cache_level=4;
EXPLAIN
SELECT t2.v FROM t1, t2, t3 WHERE t3.v <> t2.v AND t3.pk = t2.i AND t1.v = t3.v
GROUP BY t2.v ORDER BY t1.pk,t2.v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ALL idx1 NULL NULL NULL 20 Using temporary; Using filesort
1 SIMPLE t3 eq_ref PRIMARY,idx2 PRIMARY 4 test.t2.i 1 Using where; Using join buffer (flat, BNLH join)
1 SIMPLE t1 ref idx2 idx2 3 test.t3.v 2 Using join buffer (incremental, BNLH join)
SELECT t2.v FROM t1, t2, t3 WHERE t3.v <> t2.v AND t3.pk = t2.i AND t1.v = t3.v
GROUP BY t2.v ORDER BY t1.pk,t2.v;
v
h
z
n
v
p
DROP TABLE t1,t2,t3;
SET SESSION join_cache_level=DEFAULT;
#
# Bug #668290: hash join with non-binary collations
#
CREATE TABLE t1 (
i int DEFAULT NULL,
cl varchar(10) CHARACTER SET latin1 DEFAULT NULL,
cu varchar(10) CHARACTER SET utf8 DEFAULT NULL,
INDEX cl (cl),
INDEX cu (cu)
);
INSERT INTO t1 VALUES
(650903552,'cmxffkpsel','z'), (535298048,'tvtjrcmxff','y'),
(1626865664,'when','for'), (39649280,'rcvljitvtj','ercvljitvt'),
(792068096,'ttercvljit','jttercvlji');
INSERT INTO t1 SELECT * FROM t1;
CREATE TABLE t2 (
cu varchar(10) CHARACTER SET utf8 DEFAULT NULL,
i int DEFAULT NULL,
cl varchar(10) CHARACTER SET latin1 DEFAULT NULL,
INDEX cu (cu),
INDEX cl (cl)
);
INSERT INTO t2 VALUES
('g',7,'like'), ('fujttercvl',6,'y'),
('s',2,'e'), ('didn\'t',0,'v'),
('gvdrodpedk',8,'chogvdrodp'), ('jichogvdro',7,'will');
EXPLAIN
SELECT t2.i FROM t1,t2 WHERE t1.cu = t2.cl ;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ALL NULL NULL NULL NULL 6
1 SIMPLE t1 ref cu cu 33 func 2 Using where; Using index
SELECT t2.i FROM t1,t2 WHERE t1.cu = t2.cl ;
i
6
6
SET SESSION join_cache_level = 4;
EXPLAIN
SELECT t2.i FROM t1,t2 WHERE t1.cu = t2.cl ;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ALL NULL NULL NULL NULL 6
1 SIMPLE t1 ref cu cu 33 func 2 Using where; Using index
SELECT t2.i FROM t1,t2 WHERE t1.cu = t2.cl ;
i
6
6
SET SESSION join_cache_level = DEFAULT;
DROP TABLE t1,t2;
#
# Bug #669382: hash join using a ref with constant key parts
#
CREATE TABLE t1 (a int);
INSERT INTO t1 VALUES
(9), (11), (7), (8), (4), (1), (12), (3), (5);
INSERT INTO t1 SELECT * FROM t1;
INSERT INTO t1 SELECT * FROM t1;
CREATE TABLE t2 (a int, b int, c int, INDEX idx (a,b));
INSERT INTO t2 VALUES
(8, 80, 800), (1, 10, 100), (1, 11, 101), (3, 30, 300),
(1, 12, 102), (8, 81, 801), (7, 70, 700), (12, 120, 1200),
(8, 82, 802), (1, 13, 103), (1, 14, 104), (3, 31, 301),
(1, 15, 105), (8, 83, 803), (7, 71, 701);
SET SESSION join_cache_level = 4;
SET SESSION join_buffer_size = 192;
EXPLAIN
SELECT t1.a, t2.c FROM t1,t2 WHERE t1.a=t2.a AND t2.b=99;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 36 Using where
1 SIMPLE t2 ref idx idx 10 test.t1.a,const 2 Using join buffer (flat, BNLH join)
SELECT t1.a, t2.c FROM t1,t2 WHERE t1.a=t2.a AND t2.b=99;
a c
SET SESSION join_cache_level = DEFAULT;
SET SESSION join_buffer_size = DEFAULT;
DROP TABLE t1,t2;
#
# Bug #671901: hash join using a ref to a varchar field
#
CREATE TABLE t1 (
v varchar(10) CHARACTER SET latin1 COLLATE latin1_bin DEFAULT NULL,
i int DEFAULT NULL
);
INSERT INTO t1 VALUES
('k',8), ('abcdefjh',-575340544), ('f',77), ('because', 2), ('f',-517472256),
('abcdefjhj',5), ('z',7);
CREATE TABLE t2 (
v varchar(10) CHARACTER SET latin1 COLLATE latin1_bin DEFAULT NULL,
i int DEFAULT NULL,
INDEX idx (v)
);
INSERT INTO t2 VALUES
('did',5), ('was',-1631322112), ('are',3), ('abcdefjhjk',3),
('abcdefjhjk',4), ('tell',-824573952), ('t',0),('v',-1711013888),
('abcdefjhjk',1015414784), ('or',4), ('now',0), ('abcdefjhjk',-32702464),
('abcdefjhjk',4), ('time',1078394880), ('f',4), ('m',-1845559296),
('ff', 5), ('abcdefjhjk',-1074397184);
EXPLAIN
SELECT t1.v,t2.i FROM t1,t2 WHERE t2.v = t1.v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 7 Using where
1 SIMPLE t2 ref idx idx 13 test.t1.v 2
SELECT t1.v,t2.i FROM t1,t2 WHERE t2.v = t1.v;
v i
f 4
f 4
EXPLAIN
SELECT t1.v,t2.i FROM t1,t2 WHERE t2.v = concat(t1.v, t1.v);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 7
1 SIMPLE t2 ref idx idx 13 func 2 Using index condition
SELECT t1.v,t2.i FROM t1,t2 WHERE t2.v = concat(t1.v, t1.v);
v i
f 5
f 5
SET SESSION join_cache_level = 4;
EXPLAIN
SELECT t1.v,t2.i FROM t1,t2 WHERE t2.v = t1.v;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 7 Using where
1 SIMPLE t2 ref idx idx 13 test.t1.v 2 Using join buffer (flat, BNLH join)
SELECT t1.v,t2.i FROM t1,t2 WHERE t2.v = t1.v;
v i
f 4
f 4
EXPLAIN
SELECT t1.v,t2.i FROM t1,t2 WHERE t2.v = concat(t1.v, t1.v);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 7
1 SIMPLE t2 ref idx idx 13 func 2 Using where; Using join buffer (flat, BNLH join)
SELECT t1.v,t2.i FROM t1,t2 WHERE t2.v = concat(t1.v, t1.v);
v i
f 5
f 5
SET SESSION join_cache_level = DEFAULT;
DROP TABLE t1,t2;
# Bug #672497: 3 way join with tiny incremental join buffer with
# and a ref access from the first table
#
CREATE TABLE t1 (
pk int PRIMARY KEY,
v varchar(10) CHARACTER SET latin1 COLLATE latin1_bin DEFAULT NULL,
INDEX idx (v)
);
INSERT INTO t1 VALUES
(1,'abcdefjhjk'), (2,'i'),(3,'abcdefjhjk'), (4,'well'), (5,'abcdefjhjk'),
(6,'abcdefjhjk'), (7,'that');
CREATE TABLE t2 (
pk int PRIMARY KEY,
i int DEFAULT NULL,
v varchar(1000) CHARACTER SET latin1 COLLATE latin1_bin DEFAULT NULL,
INDEX idx (v)
);
INSERT INTO t2 VALUES
(1,6,'yes'), (2,NULL,'will'), (3,NULL,'o'), (4,NULL,'k'), (5,NULL,'she'),
(6,-1450835968,'abcdefjhjkl'), (7,-975831040,'abcdefjhjkl'), (8,NULL,'z'),
(10,-343932928,'t'),
(11,6,'yes'), (12,NULL,'will'), (13,NULL,'o'), (14,NULL,'k'), (15,NULL,'she'),
(16,-1450835968,'abcdefjhjkl'), (17,-975831040,'abcdefjhjkl'), (18,NULL,'z'),
(19,-343932928,'t');
CREATE TABLE t3 (
pk int NOT NULL PRIMARY KEY,
i int,
v varchar(1024) CHARACTER SET utf8 COLLATE utf8_bin DEFAULT NULL,
INDEX idx (v(333))
);
INSERT INTO t3 VALUES
(1,7,'abcdefjhjkl'),(2,6,'y'), (3,NULL,'to'),(4,7,'n'),(5,7,'look'), (6,NULL,'all'),
(7,1443168256,'c'), (8,1427046400,'right'),
(11,7,'abcdefjhjkl'), (12,6,'y'), (13,NULL,'to'), (14,7,'n'), (15,7,'look'),
(16,NULL,'all'), (17,1443168256,'c'), (18,1427046400,'right'),
(21,7,'abcdefjhjkl'), (22,6,'y'), (23,NULL,'to'), (24,7,'n'), (25,7,'look'),
(26,NULL,'all'), (27,1443168256,'c'), (28,1427046400,'right'),
(31,7,'abcdefjhjkl'), (32,6,'y'), (33,NULL,'to'), (34,7,'n'), (35,7,'look'),
(36,NULL,'all'), (37,1443168256,'c'), (38,1427046400,'right');
SET SESSION join_buffer_size = 192;
SET SESSION join_cache_level = 4;
EXPLAIN
SELECT t3.i FROM t1,t2,t3
WHERE t1.v = t2.v AND t3.v = t1.v AND t2.i <> 0;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 index idx idx 13 NULL 7 Using where; Using index
1 SIMPLE t2 ref idx idx 1003 test.t1.v 2 Using where; Using join buffer (flat, BNLH join)
1 SIMPLE t3 ref idx idx 1002 func 3 Using where; Using join buffer (incremental, BNLH join)
SELECT t3.i FROM t1,t2,t3
WHERE t1.v = t2.v AND t3.v = t1.v AND t2.i <> 0;
i
SET SESSION join_cache_level = DEFAULT;
SET SESSION join_buffer_size = DEFAULT;
DROP TABLE t1,t2,t3;
#
# Bug #672551: hash join over a long varchar field
#
CREATE TABLE t1 (
pk int PRIMARY KEY,
a varchar(512) CHARSET latin1 COLLATE latin1_bin DEFAULT NULL,
INDEX idx (a)
);
INSERT INTO t1 VALUES (2, 'aa'), (5, 'ccccccc'), (3, 'bb');
CREATE TABLE t2(
pk int PRIMARY KEY,
a varchar(512) CHARSET latin1 COLLATE latin1_bin DEFAULT NULL,
INDEX idx (a)
);
INSERT INTO t2 VALUES
(10, 'a'), (20, 'c'), (30, 'aa'), (4, 'bb'),
(11, 'a'), (21, 'c'), (31, 'aa'), (41, 'cc'),
(12, 'a'), (22, 'c'), (32, 'bb'), (42, 'aa');
SELECT * FROM t1,t2 WHERE t2.a=t1.a;
pk a pk a
2 aa 30 aa
2 aa 31 aa
2 aa 42 aa
3 bb 4 bb
3 bb 32 bb
SET SESSION join_cache_level = 4;
EXPLAIN
SELECT * FROM t1,t2 WHERE t2.a=t1.a;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL idx NULL NULL NULL 3 Using where
1 SIMPLE t2 ref idx idx 515 test.t1.a 2 Using join buffer (flat, BNLH join)
SELECT * FROM t1,t2 WHERE t2.a=t1.a;
pk a pk a
2 aa 30 aa
3 bb 4 bb
2 aa 31 aa
3 bb 32 bb
2 aa 42 aa
SET SESSION join_cache_level = DEFAULT;
DROP TABLE t1,t2;
#
# Bug #674431: nested outer join when join_cache_level is set to 7
#
CREATE TABLE t1 (a int, b varchar(32)) ;
INSERT INTO t1 VALUES (5,'h'), (NULL,'j');
CREATE TABLE t2 (a int, b varchar(32), c int) ;
INSERT INTO t2 VALUES (5,'h',100), (NULL,'j',200);
CREATE TABLE t3 (a int, b varchar(32), INDEX idx(b));
INSERT INTO t3 VALUES (77,'h'), (88,'g');
SET SESSION optimizer_switch = 'outer_join_with_cache=on';
SET SESSION join_cache_level = 7;
SELECT t3.a
FROM t1 LEFT JOIN
(t2 LEFT OUTER JOIN t3 ON t2.b = t3.b) ON t2.a = t1.b
WHERE t3.a BETWEEN 3 AND 11 OR t1.a <= t2.c;
a
SET SESSION optimizer_switch = 'outer_join_with_cache=off';
SET SESSION join_cache_level = DEFAULT;
DROP TABLE t1,t2,t3;
#
# Bug #52540: nested outer join when join_cache_level is set to 3
#
CREATE TABLE t1 (a int);
INSERT INTO t1 VALUES (2);
CREATE TABLE t2 (a varchar(10));
INSERT INTO t2 VALUES ('f'),('x');
CREATE TABLE t3 (pk int(11) PRIMARY KEY);
INSERT INTO t3 VALUES (2);
CREATE TABLE t4 (a varchar(10));
SET SESSION optimizer_switch = 'outer_join_with_cache=on';
SET SESSION join_cache_level = 3;
SELECT *
FROM t2 LEFT JOIN
((t1 JOIN t3 ON t1.a = t3.pk) LEFT JOIN t4 ON 1) ON 1;
a a pk a
f 2 2 NULL
x 2 2 NULL
SET SESSION optimizer_switch = 'outer_join_with_cache=off';
SET SESSION join_cache_level = DEFAULT;
DROP TABLE t1,t2,t3,t4;
#
# Bug #674423: outer join with ON expression over only outer tables
#
CREATE TABLE t1 (a int) ;
INSERT INTO t1 VALUES ('9');
CREATE TABLE t2 (pk int, a int) ;
INSERT INTO t2 VALUES ('9',NULL), ('1',NULL);
SET SESSION optimizer_switch = 'outer_join_with_cache=on';
SET SESSION join_cache_level = 0;
EXPLAIN
SELECT * FROM t2 LEFT JOIN t1 ON t2.a <> 0 WHERE t1.a <> 0 OR t2.pk < 9;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ALL NULL NULL NULL NULL 2
1 SIMPLE t1 ALL NULL NULL NULL NULL 1 Using where
SELECT * FROM t2 LEFT JOIN t1 ON t2.a <> 0 WHERE t1.a <>0 OR t2.pk < 9;
pk a a
1 NULL NULL
SET SESSION join_cache_level = 1;
EXPLAIN
SELECT * FROM t2 LEFT JOIN t1 ON t2.a <> 0 WHERE t1.a <> 0 OR t2.pk < 9;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ALL NULL NULL NULL NULL 2
1 SIMPLE t1 ALL NULL NULL NULL NULL 1 Using where; Using join buffer (flat, BNL join)
SELECT * FROM t2 LEFT JOIN t1 ON t2.a <> 0 WHERE t1.a <> 0 OR t2.pk < 9;
pk a a
1 NULL NULL
SET SESSION optimizer_switch = 'outer_join_with_cache=off';
SET SESSION join_cache_level = DEFAULT;
DROP TABLE t1,t2;
#
# Bug #675095: nested outer join using join buffer
#
CREATE TABLE t1 (pk int, a1 int) ;
INSERT IGNORE INTO t1 VALUES (2,NULL), (8,0);
CREATE TABLE t2 (pk int, a2 int, c2 int, d2 int) ;
INSERT IGNORE INTO t2 VALUES (9,0,0,2), (1,0,0,7);
CREATE TABLE t3 (pk int, a3 int, c3 int, d3 int) ;
INSERT IGNORE INTO t3 VALUES (9,0,0,2), (1,0,0,7);
CREATE TABLE t4 (pk int, a4 int, INDEX idx(a4)) ;
INSERT IGNORE INTO t4 VALUES (2,NULL), (8,0);
CREATE TABLE t5 (pk int, a5 int) ;
INSERT IGNORE INTO t5 VALUES (2,0), (8,0);
SET SESSION optimizer_switch = 'outer_join_with_cache=on';
SET SESSION join_cache_level = 0;
EXPLAIN EXTENDED
SELECT *
FROM ((t1 LEFT JOIN (t2 JOIN t3 ON t2.c2 = t3.a3) ON t1.pk = t2.d2)
LEFT JOIN t4 ON t1.a1 = t4.a4) LEFT JOIN t5 ON t3.a3 = t5.a5;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00
1 SIMPLE t2 ALL NULL NULL NULL NULL 2 100.00 Using where
1 SIMPLE t3 ALL NULL NULL NULL NULL 2 100.00 Using where
1 SIMPLE t4 ref idx idx 5 test.t1.a1 2 100.00 Using where
1 SIMPLE t5 ALL NULL NULL NULL NULL 2 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`pk` AS `pk`,`test`.`t1`.`a1` AS `a1`,`test`.`t2`.`pk` AS `pk`,`test`.`t2`.`a2` AS `a2`,`test`.`t2`.`c2` AS `c2`,`test`.`t2`.`d2` AS `d2`,`test`.`t3`.`pk` AS `pk`,`test`.`t3`.`a3` AS `a3`,`test`.`t3`.`c3` AS `c3`,`test`.`t3`.`d3` AS `d3`,`test`.`t4`.`pk` AS `pk`,`test`.`t4`.`a4` AS `a4`,`test`.`t5`.`pk` AS `pk`,`test`.`t5`.`a5` AS `a5` from `test`.`t1` left join (`test`.`t2` join `test`.`t3`) on(((`test`.`t2`.`d2` = `test`.`t1`.`pk`) and (`test`.`t3`.`a3` = `test`.`t2`.`c2`))) left join `test`.`t4` on(((`test`.`t4`.`a4` = `test`.`t1`.`a1`) and (`test`.`t1`.`a1` is not null))) left join `test`.`t5` on((`test`.`t5`.`a5` = `test`.`t3`.`a3`)) where 1
SELECT *
FROM ((t1 LEFT JOIN (t2 JOIN t3 ON t2.c2 = t3.a3) ON t1.pk = t2.d2)
LEFT JOIN t4 ON t1.a1 = t4.a4) LEFT JOIN t5 ON t3.a3 = t5.a5;
pk a1 pk a2 c2 d2 pk a3 c3 d3 pk a4 pk a5
2 NULL 9 0 0 2 9 0 0 2 NULL NULL 2 0
2 NULL 9 0 0 2 9 0 0 2 NULL NULL 8 0
2 NULL 9 0 0 2 1 0 0 7 NULL NULL 2 0
2 NULL 9 0 0 2 1 0 0 7 NULL NULL 8 0
8 0 NULL NULL NULL NULL NULL NULL NULL NULL 8 0 NULL NULL
SET SESSION join_cache_level = 2;
EXPLAIN EXTENDED
SELECT *
FROM ((t1 LEFT JOIN (t2 JOIN t3 ON t2.c2 = t3.a3) ON t1.pk = t2.d2)
LEFT JOIN t4 ON t1.a1 = t4.a4) LEFT JOIN t5 ON t3.a3 = t5.a5;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00
1 SIMPLE t2 ALL NULL NULL NULL NULL 2 100.00 Using where; Using join buffer (flat, BNL join)
1 SIMPLE t3 ALL NULL NULL NULL NULL 2 100.00 Using where; Using join buffer (incremental, BNL join)
1 SIMPLE t4 ref idx idx 5 test.t1.a1 2 100.00 Using where
1 SIMPLE t5 ALL NULL NULL NULL NULL 2 100.00 Using where; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select `test`.`t1`.`pk` AS `pk`,`test`.`t1`.`a1` AS `a1`,`test`.`t2`.`pk` AS `pk`,`test`.`t2`.`a2` AS `a2`,`test`.`t2`.`c2` AS `c2`,`test`.`t2`.`d2` AS `d2`,`test`.`t3`.`pk` AS `pk`,`test`.`t3`.`a3` AS `a3`,`test`.`t3`.`c3` AS `c3`,`test`.`t3`.`d3` AS `d3`,`test`.`t4`.`pk` AS `pk`,`test`.`t4`.`a4` AS `a4`,`test`.`t5`.`pk` AS `pk`,`test`.`t5`.`a5` AS `a5` from `test`.`t1` left join (`test`.`t2` join `test`.`t3`) on(((`test`.`t2`.`d2` = `test`.`t1`.`pk`) and (`test`.`t3`.`a3` = `test`.`t2`.`c2`))) left join `test`.`t4` on(((`test`.`t4`.`a4` = `test`.`t1`.`a1`) and (`test`.`t1`.`a1` is not null))) left join `test`.`t5` on((`test`.`t5`.`a5` = `test`.`t3`.`a3`)) where 1
SELECT *
FROM ((t1 LEFT JOIN (t2 JOIN t3 ON t2.c2 = t3.a3) ON t1.pk = t2.d2)
LEFT JOIN t4 ON t1.a1 = t4.a4) LEFT JOIN t5 ON t3.a3 = t5.a5;
pk a1 pk a2 c2 d2 pk a3 c3 d3 pk a4 pk a5
2 NULL 9 0 0 2 9 0 0 2 NULL NULL 2 0
2 NULL 9 0 0 2 1 0 0 7 NULL NULL 2 0
2 NULL 9 0 0 2 9 0 0 2 NULL NULL 8 0
2 NULL 9 0 0 2 1 0 0 7 NULL NULL 8 0
8 0 NULL NULL NULL NULL NULL NULL NULL NULL 8 0 NULL NULL
SET SESSION join_cache_level = 1;
EXPLAIN EXTENDED
SELECT *
FROM ((t1 LEFT JOIN (t2 JOIN t3 ON t2.c2 = t3.a3) ON t1.pk = t2.d2)
LEFT JOIN t4 ON t1.a1 = t4.a4) LEFT JOIN t5 ON t3.a3 = t5.a5;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2 100.00
1 SIMPLE t2 ALL NULL NULL NULL NULL 2 100.00 Using where
1 SIMPLE t3 ALL NULL NULL NULL NULL 2 100.00 Using where
1 SIMPLE t4 ref idx idx 5 test.t1.a1 2 100.00 Using where
1 SIMPLE t5 ALL NULL NULL NULL NULL 2 100.00 Using where; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select `test`.`t1`.`pk` AS `pk`,`test`.`t1`.`a1` AS `a1`,`test`.`t2`.`pk` AS `pk`,`test`.`t2`.`a2` AS `a2`,`test`.`t2`.`c2` AS `c2`,`test`.`t2`.`d2` AS `d2`,`test`.`t3`.`pk` AS `pk`,`test`.`t3`.`a3` AS `a3`,`test`.`t3`.`c3` AS `c3`,`test`.`t3`.`d3` AS `d3`,`test`.`t4`.`pk` AS `pk`,`test`.`t4`.`a4` AS `a4`,`test`.`t5`.`pk` AS `pk`,`test`.`t5`.`a5` AS `a5` from `test`.`t1` left join (`test`.`t2` join `test`.`t3`) on(((`test`.`t2`.`d2` = `test`.`t1`.`pk`) and (`test`.`t3`.`a3` = `test`.`t2`.`c2`))) left join `test`.`t4` on(((`test`.`t4`.`a4` = `test`.`t1`.`a1`) and (`test`.`t1`.`a1` is not null))) left join `test`.`t5` on((`test`.`t5`.`a5` = `test`.`t3`.`a3`)) where 1
SELECT *
FROM ((t1 LEFT JOIN (t2 JOIN t3 ON t2.c2 = t3.a3) ON t1.pk = t2.d2)
LEFT JOIN t4 ON t1.a1 = t4.a4) LEFT JOIN t5 ON t3.a3 = t5.a5;
pk a1 pk a2 c2 d2 pk a3 c3 d3 pk a4 pk a5
2 NULL 9 0 0 2 9 0 0 2 NULL NULL 2 0
2 NULL 9 0 0 2 1 0 0 7 NULL NULL 2 0
2 NULL 9 0 0 2 9 0 0 2 NULL NULL 8 0
2 NULL 9 0 0 2 1 0 0 7 NULL NULL 8 0
8 0 NULL NULL NULL NULL NULL NULL NULL NULL 8 0 NULL NULL
SET SESSION optimizer_switch = 'outer_join_with_cache=off';
SET SESSION join_cache_level = DEFAULT;
DROP TABLE t1,t2,t3,t4,t5;
#
# Bug #675516: nested outer join with 3 tables in the nest
# using BNL + BNLH
#
CREATE TABLE t1 (a1 int, b1 int, c1 int) ;
INSERT INTO t1 VALUES (7,8,0), (6,4,0);
CREATE TABLE t2 (a2 int) ;
INSERT INTO t2 VALUES (5);
CREATE TABLE t3 (a3 int, b3 int, c3 int, PRIMARY KEY (b3)) ;
INSERT INTO t3 VALUES (2,5,0);
CREATE TABLE t4 (a4 int, b4 int, c4 int) ;
INSERT INTO t4 VALUES (7,8,0);
SET SESSION optimizer_switch = 'outer_join_with_cache=on';
SET SESSION join_cache_level = 4;
EXPLAIN
SELECT * FROM
t1 LEFT JOIN
((t2 JOIN t3 ON t2.a2 = t3.b3) JOIN t4 ON t4.b4 <> 0) ON t1.c1 = t3.c3
WHERE t3.a3 IS NULL;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
1 SIMPLE t2 ALL NULL NULL NULL NULL 1 Using where; Using join buffer (flat, BNL join)
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.a2 1 Using where; Using join buffer (incremental, BNLH join)
1 SIMPLE t4 ALL NULL NULL NULL NULL 1 Using where; Using join buffer (incremental, BNL join)
SELECT * FROM
t1 LEFT JOIN
((t2 JOIN t3 ON t2.a2 = t3.b3) JOIN t4 ON t4.b4 <> 0) ON t1.c1 = t3.c3
WHERE t3.a3 IS NULL;
a1 b1 c1 a2 a3 b3 c3 a4 b4 c4
SET SESSION join_cache_level = 0;
EXPLAIN
SELECT * FROM
t1 LEFT JOIN
((t2 JOIN t3 ON t2.a2 = t3.b3) JOIN t4 ON t4.b4 <> 0) ON t1.c1 = t3.c3
WHERE t3.a3 IS NULL;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
1 SIMPLE t2 ALL NULL NULL NULL NULL 1 Using where
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.a2 1 Using where
1 SIMPLE t4 ALL NULL NULL NULL NULL 1 Using where
SELECT * FROM
t1 LEFT JOIN
((t2 JOIN t3 ON t2.a2 = t3.b3) JOIN t4 ON t4.b4 <> 0) ON t1.c1 = t3.c3
WHERE t3.a3 IS NULL;
a1 b1 c1 a2 a3 b3 c3 a4 b4 c4
SET SESSION optimizer_switch = 'outer_join_with_cache=off';
SET SESSION join_cache_level = DEFAULT;
DROP TABLE t1,t2,t3,t4;
#
# Bug #660963: nested outer join with join_cache_level set to 5
#
CREATE TABLE t1 (a1 int) ;
INSERT INTO t1 VALUES (0),(0);
CREATE TABLE t2 (a2 int, b2 int, PRIMARY KEY (a2)) ;
INSERT INTO t2 VALUES (2,1);
CREATE TABLE t3 (a3 int, b3 int, PRIMARY KEY (a3)) ;
INSERT INTO t3 VALUES (2,1);
SET SESSION optimizer_switch = 'outer_join_with_cache=on';
SET SESSION join_cache_level = 6;
EXPLAIN
SELECT * FROM t1 LEFT JOIN t2 JOIN t3 ON t3.a3 = t2.a2 ON t3.b3 <> 0 ;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
1 SIMPLE t2 ALL PRIMARY NULL NULL NULL 1 Using where; Using join buffer (flat, BNL join)
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.a2 1 Using where; Using join buffer (incremental, BKA join)
SELECT * FROM t1 LEFT JOIN t2 JOIN t3 ON t3.a3 = t2.a2 ON t3.b3 <> 0 ;
a1 a2 b2 a3 b3
0 2 1 2 1
0 2 1 2 1
SET SESSION join_cache_level = 5;
EXPLAIN
SELECT * FROM t1 LEFT JOIN t2 JOIN t3 ON t3.a3 = t2.a2 ON t3.b3 <> 0 ;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
1 SIMPLE t2 ALL PRIMARY NULL NULL NULL 1 Using where; Using join buffer (flat, BNL join)
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.a2 1 Using where; Using join buffer (incremental, BNLH join)
SELECT * FROM t1 LEFT JOIN t2 JOIN t3 ON t3.a3 = t2.a2 ON t3.b3 <> 0 ;
a1 a2 b2 a3 b3
0 2 1 2 1
0 2 1 2 1
SET SESSION optimizer_switch = 'outer_join_with_cache=off';
SET SESSION join_cache_level = DEFAULT;
DROP TABLE t1,t2,t3;
#
# Bug #675922: incremental buffer for BKA with access from previous
# buffers from non-nullable columns whose values may be null
#
CREATE TABLE t1 (a1 varchar(32)) ;
INSERT INTO t1 VALUES ('s'),('k');
CREATE TABLE t2 (a2 int PRIMARY KEY, b2 varchar(32)) ;
INSERT INTO t2 VALUES (7,'s');
CREATE TABLE t3 (a3 int PRIMARY KEY, b3 varchar(32)) ;
INSERT INTO t3 VALUES (7,'s');
CREATE TABLE t4 (a4 int) ;
INSERT INTO t4 VALUES (9);
CREATE TABLE t5(a5 int PRIMARY KEY, b5 int) ;
INSERT INTO t5 VALUES (7,0);
SET SESSION optimizer_switch = 'outer_join_with_cache=on';
SET SESSION join_cache_level = 0;
EXPLAIN
SELECT t4.a4, t5.b5
FROM ((t1 LEFT JOIN (t2 JOIN t3 ON t2.a2 = t3.a3) ON t2.b2 = t1.a1)
LEFT JOIN t4 ON t4.a4 <> 0) LEFT JOIN t5 ON t5.a5 = t2.a2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
1 SIMPLE t2 ALL PRIMARY NULL NULL NULL 1 Using where
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.a2 1 Using index
1 SIMPLE t4 ALL NULL NULL NULL NULL 1 Using where
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t2.a2 1 Using where
SELECT t4.a4, t5.b5
FROM ((t1 LEFT JOIN (t2 JOIN t3 ON t2.a2 = t3.a3) ON t2.b2 = t1.a1)
LEFT JOIN t4 ON t4.a4 <> 0) LEFT JOIN t5 ON t5.a5 = t2.a2;
a4 b5
9 0
9 NULL
SET SESSION join_cache_level = 6;
EXPLAIN
SELECT t4.a4, t5.b5
FROM ((t1 LEFT JOIN (t2 JOIN t3 ON t2.a2 = t3.a3) ON t2.b2 = t1.a1)
LEFT JOIN t4 ON t4.a4 <> 0) LEFT JOIN t5 ON t5.a5 = t2.a2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
1 SIMPLE t2 ALL PRIMARY NULL NULL NULL 1 Using where
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 4 test.t2.a2 1 Using index
1 SIMPLE t4 ALL NULL NULL NULL NULL 1 Using where; Using join buffer (flat, BNL join)
1 SIMPLE t5 eq_ref PRIMARY PRIMARY 4 test.t2.a2 1 Using where; Using join buffer (incremental, BKA join)
SELECT t4.a4, t5.b5
FROM ((t1 LEFT JOIN (t2 JOIN t3 ON t2.a2 = t3.a3) ON t2.b2 = t1.a1)
LEFT JOIN t4 ON t4.a4 <> 0) LEFT JOIN t5 ON t5.a5 = t2.a2;
a4 b5
9 0
9 NULL
SET SESSION optimizer_switch = 'outer_join_with_cache=off';
SET SESSION join_cache_level = DEFAULT;
DROP TABLE t1,t2,t3,t4,t5;
set @@optimizer_switch=@save_optimizer_switch;
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