DROP TABLE IF EXISTS t1,t2,t3,t4,t5,t6,t7,t8,t9,t10,t11; DROP DATABASE IF EXISTS world; 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 ); 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' ); CREATE TABLE CountryLanguage ( Country char(3) NOT NULL default '', Language char(30) NOT NULL default '', Percentage float(3,1) NOT NULL default '0.0' ); 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 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 1 SIMPLE City ALL NULL NULL NULL NULL 4079 Using where; Using join buffer 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 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 1 SIMPLE City ALL NULL NULL NULL NULL 4079 Using where; Using join buffer 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 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 1 SIMPLE City ALL NULL NULL NULL NULL 4079 Using where; Using join buffer 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 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 1 SIMPLE City ALL NULL NULL NULL NULL 4079 Using where; Using join buffer 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) ); 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) ); 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) ); 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 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 1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition(BKA); Using where; Using join buffer 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 # !!!NB igor: after backporting the SJ code the following should return # 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 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 City ALL Population NULL NULL NULL 4079 Using where 2 DEPENDENT SUBQUERY Country unique_subquery PRIMARY,Name PRIMARY 3 func 1 Using where 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 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 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 1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition(BKA); Using where; Using join buffer 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 # !!!NB igor: after backporting the SJ code the following should return # 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 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 City ALL Population NULL NULL NULL 4079 Using where 2 DEPENDENT SUBQUERY Country unique_subquery PRIMARY,Name PRIMARY 3 func 1 Using where 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 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 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 1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition(BKA); Using where; Using join buffer 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 # !!!NB igor: after backporting the SJ code the following should return # 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 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 City ALL Population NULL NULL NULL 4079 Using where 2 DEPENDENT SUBQUERY Country unique_subquery PRIMARY,Name PRIMARY 3 func 1 Using where 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 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 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 1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition(BKA); Using where; Using join buffer 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 # !!!NB igor: after backporting the SJ code the following should return # 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 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 City ALL Population NULL NULL NULL 4079 Using where 2 DEPENDENT SUBQUERY Country unique_subquery PRIMARY,Name PRIMARY 3 func 1 Using where 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 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=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 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 1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition(BKA); Using where; Using join buffer 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 # !!!NB igor: after backporting the SJ code the following should return # 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 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 City ALL Population NULL NULL NULL 4079 Using where 2 DEPENDENT SUBQUERY Country unique_subquery PRIMARY,Name PRIMARY 3 func 1 Using where 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 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 1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition(BKA); Using where; Using join buffer 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 # !!!NB igor: after backporting the SJ code the following should return # 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 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 City ALL Population NULL NULL NULL 4079 Using where 2 DEPENDENT SUBQUERY Country unique_subquery PRIMARY,Name PRIMARY 3 func 1 Using where 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 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 1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition(BKA); Using where; Using join buffer 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 # !!!NB igor: after backporting the SJ code the following should return # 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 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 City ALL Population NULL NULL NULL 4079 Using where 2 DEPENDENT SUBQUERY Country unique_subquery PRIMARY,Name PRIMARY 3 func 1 Using where 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 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 1 SIMPLE City ref Country Country 3 world.Country.Code 18 Using index condition(BKA); Using where; Using join buffer 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 # !!!NB igor: after backporting the SJ code the following should return # 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 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 City ALL Population NULL NULL NULL 4079 Using where 2 DEPENDENT SUBQUERY Country unique_subquery PRIMARY,Name PRIMARY 3 func 1 Using where 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=256; 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 SELECT City.Name, Country.Name FROM City,Country WHERE City.Country=Country.Code AND City.Population > 3000000; Name Name Sydney Australia Dhaka Bangladesh Rio de Janeiro Brazil São Paulo Brazil London United Kingdom Santiago de Chile Chile Alexandria Egypt Cairo Egypt Jakarta Indonesia Delhi India Calcutta [Kolkata] India Mumbai (Bombay) India Chennai (Madras) India Baghdad Iraq Teheran Iran Tokyo Japan Jokohama [Yokohama] Japan Peking China Chongqing China Shanghai China Wuhan China Harbin China Shenyang China Kanton [Guangzhou] China Tianjin 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 Ankara Turkey Istanbul Turkey St Petersburg Russian Federation Moscow Russian Federation Ho Chi Minh City Vietnam Los Angeles United States New York United States 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 1 SIMPLE t5 eq_ref PRIMARY,t5_formattypeid PRIMARY 4 test.t4.formatclassid 1 Using where; Using join buffer 1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.metaid 1 Using join buffer 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 1 SIMPLE t8 eq_ref PRIMARY PRIMARY 4 test.t7.artistid 1 Using join buffer 1 SIMPLE t9 index PRIMARY,t9_subgenreid,t9_metaid PRIMARY 8 NULL 2 Using where; Using index; Using join buffer 1 SIMPLE t10 eq_ref PRIMARY,t10_genreid PRIMARY 4 test.t9.subgenreid 1 Using join buffer 1 SIMPLE t11 eq_ref PRIMARY PRIMARY 4 test.t10.genreid 1 Using join buffer 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 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 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 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 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 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 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= 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 1 SIMPLE t2 ref f1 f1 4 test.t1.f1 3 Using index condition(BKA); Using join buffer 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 1 SIMPLE t2 ref f1 f1 4 test.t1.f1 3 Using index condition(BKA); Using join buffer 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 1 SIMPLE t2 ref f1 f1 4 test.t1.f1 3 Using index condition(BKA); Using join buffer 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 1 SIMPLE t2 ref f1 f1 4 test.t1.f1 3 Using index condition(BKA); Using join buffer 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 index; Using temporary; Using filesort 1 SIMPLE t2 ref idx2 idx2 5 test.t1.id1 2 Using join buffer 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 index; Using temporary; Using filesort 1 SIMPLE t2 ref idx2 idx2 5 test.t1.id1 2 Using where; Using join buffer 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 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 1 SIMPLE t2 ref idx idx 5 test.t1.b 1 Using join buffer 1 SIMPLE t3 ref idx idx 5 test.t1.d 1 Using join buffer 1 SIMPLE t4 ref idx idx 5 test.t1.c 1 Using join buffer 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 1 SIMPLE t2 eq_ref PRIMARY PRIMARY 8 test.t1.id3 1 Using join buffer 1 SIMPLE t3 eq_ref PRIMARY PRIMARY 8 test.t2.id4 1 Using where; Using join buffer 1 SIMPLE t4 eq_ref PRIMARY PRIMARY 8 test.t1.id2 1 Using join buffer 1 SIMPLE t5 eq_ref PRIMARY PRIMARY 16 test.t1.id1,test.t1.id2 1 Using where; Using join buffer 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 15 AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA 2567095402 2667134182 0 228172702 3 AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA 2567095402 2667134182 0 228172702 134 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 17 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0 228808822 50 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0 228808822 18 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0 228808822 1 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0 228808822 3 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0 228808822 4 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 826928662 935693782 0 228808822 89 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0 228808822 19 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0 228808822 84 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0 228808822 14 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC 2381969632 2482416112 0 228808822 9 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 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 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;