mirror of
https://github.com/MariaDB/server.git
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3beeb5d045
ORDER BY computed col
GROUP BY implies ORDER BY in the MySQL dialect of SQL. Therefore, when an
index on the first table in the query is used, and that index satisfies
ordering according to the GROUP BY clause, the query optimizer estimates the
number of tuples that need to be read from this index. If there is a LIMIT
clause, table statistics on tables following this 'sort table' are employed.
There may be a separate ORDER BY clause however, which mandates reading the
whole 'sort table' anyway. But the previous estimate was left untouched.
Fixed by removing the estimate from EXPLAIN output if GROUP BY is used in
conjunction with an ORDER BY clause that mandates using a temporary table.
1641 lines
44 KiB
Text
1641 lines
44 KiB
Text
drop table if exists t1,t2,t3;
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CREATE TABLE t1 (
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id int(6) DEFAULT '0' NOT NULL,
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idservice int(5),
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clee char(20) NOT NULL,
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flag char(1),
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KEY id (id),
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PRIMARY KEY (clee)
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);
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INSERT INTO t1 VALUES (2,4,'6067169d','Y');
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INSERT INTO t1 VALUES (2,5,'606716d1','Y');
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INSERT INTO t1 VALUES (2,1,'606717c1','Y');
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INSERT INTO t1 VALUES (3,1,'6067178d','Y');
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INSERT INTO t1 VALUES (2,6,'60671515','Y');
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INSERT INTO t1 VALUES (2,7,'60671569','Y');
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INSERT INTO t1 VALUES (2,3,'dd','Y');
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CREATE TABLE t2 (
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id int(6) NOT NULL auto_increment,
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description varchar(40) NOT NULL,
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idform varchar(40),
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ordre int(6) unsigned DEFAULT '0' NOT NULL,
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image varchar(60),
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PRIMARY KEY (id),
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KEY id (id,ordre)
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);
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INSERT INTO t2 VALUES (1,'Emettre un appel d''offres','en_construction.html',10,'emettre.gif');
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INSERT INTO t2 VALUES (2,'Emettre des soumissions','en_construction.html',20,'emettre.gif');
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INSERT INTO t2 VALUES (7,'Liste des t2','t2_liste_form.phtml',51060,'link.gif');
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INSERT INTO t2 VALUES (8,'Consulter les soumissions','consulter_soumissions.phtml',200,'link.gif');
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INSERT INTO t2 VALUES (9,'Ajouter un type de materiel','typeMateriel_ajoute_form.phtml',51000,'link.gif');
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INSERT INTO t2 VALUES (10,'Lister/modifier un type de materiel','typeMateriel_liste_form.phtml',51010,'link.gif');
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INSERT INTO t2 VALUES (3,'Créer une fiche de client','clients_ajoute_form.phtml',40000,'link.gif');
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INSERT INTO t2 VALUES (4,'Modifier des clients','en_construction.html',40010,'link.gif');
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INSERT INTO t2 VALUES (5,'Effacer des clients','en_construction.html',40020,'link.gif');
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INSERT INTO t2 VALUES (6,'Ajouter un service','t2_ajoute_form.phtml',51050,'link.gif');
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select t1.id,t1.idservice,t2.ordre,t2.description from t1, t2 where t1.id = 2 and t1.idservice = t2.id order by t2.ordre;
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id idservice ordre description
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2 1 10 Emettre un appel d'offres
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2 3 40000 Créer une fiche de client
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2 4 40010 Modifier des clients
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2 5 40020 Effacer des clients
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2 6 51050 Ajouter un service
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2 7 51060 Liste des t2
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drop table t1,t2;
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create table t1 (first char(10),last char(10));
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insert into t1 values ("Michael","Widenius");
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insert into t1 values ("Allan","Larsson");
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insert into t1 values ("David","Axmark");
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select concat(first," ",last) as name from t1 order by name;
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name
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Allan Larsson
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David Axmark
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Michael Widenius
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select concat(last," ",first) as name from t1 order by name;
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name
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Axmark David
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Larsson Allan
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Widenius Michael
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drop table t1;
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create table t1 (i int);
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insert into t1 values(1),(2),(1),(2),(1),(2),(3);
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select distinct i from t1;
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i
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1
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2
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3
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select distinct i from t1 order by rand(5);
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i
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1
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3
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2
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select distinct i from t1 order by i desc;
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i
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3
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2
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1
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select distinct i from t1 order by 1-i;
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i
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3
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2
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1
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select distinct i from t1 order by mod(i,2),i;
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i
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2
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1
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3
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drop table t1;
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create table t1 ( pk int primary key, name varchar(255) not null, number varchar(255) not null);
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insert into t1 values (1, 'Gamma', '123'), (2, 'Gamma Ext', '123a'), (3, 'Alpha', '001'), (4, 'Beta', '200c');
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select distinct t1.name as 'Building Name',t1.number as 'Building Number' from t1 order by t1.name asc;
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Building Name Building Number
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Alpha 001
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Beta 200c
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Gamma 123
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Gamma Ext 123a
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drop table t1;
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create table t1 (id int not null,col1 int not null,col2 int not null,index(col1));
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insert into t1 values(1,2,2),(2,2,1),(3,1,2),(4,1,1),(5,1,4),(6,2,3),(7,3,1),(8,2,4);
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select * from t1 order by col1,col2;
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id col1 col2
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4 1 1
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3 1 2
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5 1 4
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2 2 1
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1 2 2
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6 2 3
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8 2 4
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7 3 1
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select col1 from t1 order by id;
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col1
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2
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2
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1
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1
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1
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2
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3
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2
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select col1 as id from t1 order by id;
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id
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1
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1
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1
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2
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2
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2
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2
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3
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select concat(col1) as id from t1 order by id;
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id
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1
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1
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1
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2
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2
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2
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2
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3
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drop table t1;
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CREATE TABLE t1 (id int auto_increment primary key,aika varchar(40),aikakentta timestamp);
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insert into t1 (aika) values ('Keskiviikko');
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insert into t1 (aika) values ('Tiistai');
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insert into t1 (aika) values ('Maanantai');
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insert into t1 (aika) values ('Sunnuntai');
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SELECT FIELD(SUBSTRING(t1.aika,1,2),'Ma','Ti','Ke','To','Pe','La','Su') AS test FROM t1 ORDER by test;
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test
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1
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2
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3
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7
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drop table t1;
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CREATE TABLE t1
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(
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a int unsigned NOT NULL,
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b int unsigned NOT NULL,
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c int unsigned NOT NULL,
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UNIQUE(a),
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INDEX(b),
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INDEX(c)
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);
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CREATE TABLE t2
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(
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c int unsigned NOT NULL,
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i int unsigned NOT NULL,
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INDEX(c)
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);
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CREATE TABLE t3
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(
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c int unsigned NOT NULL,
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v varchar(64),
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INDEX(c)
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);
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INSERT INTO t1 VALUES (1,1,1);
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INSERT INTO t1 VALUES (2,1,2);
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INSERT INTO t1 VALUES (3,2,1);
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INSERT INTO t1 VALUES (4,2,2);
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INSERT INTO t2 VALUES (1,50);
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INSERT INTO t2 VALUES (2,25);
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INSERT INTO t3 VALUES (1,'123 Park Place');
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INSERT INTO t3 VALUES (2,'453 Boardwalk');
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SELECT a,b,if(b = 1,i,if(b = 2,v,''))
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FROM t1
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LEFT JOIN t2 USING(c)
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LEFT JOIN t3 ON t3.c = t1.c;
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a b if(b = 1,i,if(b = 2,v,''))
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1 1 50
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2 1 25
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3 2 123 Park Place
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4 2 453 Boardwalk
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SELECT a,b,if(b = 1,i,if(b = 2,v,''))
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FROM t1
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LEFT JOIN t2 ON t1.c = t2.c
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LEFT JOIN t3 ON t3.c = t1.c;
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a b if(b = 1,i,if(b = 2,v,''))
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1 1 50
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2 1 25
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3 2 123 Park Place
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4 2 453 Boardwalk
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SELECT a,b,if(b = 1,i,if(b = 2,v,''))
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FROM t1
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LEFT JOIN t2 USING(c)
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LEFT JOIN t3 ON t3.c = t1.c
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ORDER BY a;
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a b if(b = 1,i,if(b = 2,v,''))
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1 1 50
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2 1 25
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3 2 123 Park Place
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4 2 453 Boardwalk
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SELECT a,b,if(b = 1,i,if(b = 2,v,''))
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FROM t1
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LEFT JOIN t2 ON t1.c = t2.c
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LEFT JOIN t3 ON t3.c = t1.c
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ORDER BY a;
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a b if(b = 1,i,if(b = 2,v,''))
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1 1 50
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2 1 25
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3 2 123 Park Place
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4 2 453 Boardwalk
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drop table t1,t2,t3;
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create table t1 (ID int not null primary key, TransactionID int not null);
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insert into t1 (ID, TransactionID) values (1, 87), (2, 89), (3, 92), (4, 94), (5, 486), (6, 490), (7, 753), (9, 828), (10, 832), (11, 834), (12, 840);
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create table t2 (ID int not null primary key, GroupID int not null);
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insert into t2 (ID, GroupID) values (87, 87), (89, 89), (92, 92), (94, 94), (486, 486), (490, 490),(753, 753), (828, 828), (832, 832), (834, 834), (840, 840);
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create table t3 (ID int not null primary key, DateOfAction date not null);
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insert into t3 (ID, DateOfAction) values (87, '1999-07-19'), (89, '1999-07-19'), (92, '1999-07-19'), (94, '1999-07-19'), (486, '1999-07-18'), (490, '2000-03-27'), (753, '2000-03-28'), (828, '1999-07-27'), (832, '1999-07-27'),(834, '1999-07-27'), (840, '1999-07-27');
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select t3.DateOfAction, t1.TransactionID from t1 join t2 join t3 where t2.ID = t1.TransactionID and t3.ID = t2.GroupID order by t3.DateOfAction, t1.TransactionID;
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DateOfAction TransactionID
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1999-07-18 486
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1999-07-19 87
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1999-07-19 89
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1999-07-19 92
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1999-07-19 94
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1999-07-27 828
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1999-07-27 832
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1999-07-27 834
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1999-07-27 840
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2000-03-27 490
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2000-03-28 753
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select t3.DateOfAction, t1.TransactionID from t1 join t2 join t3 where t2.ID = t1.TransactionID and t3.ID = t2.GroupID order by t1.TransactionID,t3.DateOfAction;
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DateOfAction TransactionID
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1999-07-19 87
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1999-07-19 89
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1999-07-19 92
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1999-07-19 94
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1999-07-18 486
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2000-03-27 490
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2000-03-28 753
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1999-07-27 828
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1999-07-27 832
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1999-07-27 834
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1999-07-27 840
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drop table t1,t2,t3;
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CREATE TABLE t1 (
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member_id int(11) NOT NULL auto_increment,
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inschrijf_datum varchar(20) NOT NULL default '',
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lastchange_datum varchar(20) NOT NULL default '',
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nickname varchar(20) NOT NULL default '',
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password varchar(8) NOT NULL default '',
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voornaam varchar(30) NOT NULL default '',
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tussenvoegsels varchar(10) NOT NULL default '',
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achternaam varchar(50) NOT NULL default '',
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straat varchar(100) NOT NULL default '',
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postcode varchar(10) NOT NULL default '',
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wijk varchar(40) NOT NULL default '',
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plaats varchar(50) NOT NULL default '',
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telefoon varchar(10) NOT NULL default '',
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geboortedatum date NOT NULL default '0000-00-00',
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geslacht varchar(5) NOT NULL default '',
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email varchar(80) NOT NULL default '',
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uin varchar(15) NOT NULL default '',
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homepage varchar(100) NOT NULL default '',
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internet varchar(15) NOT NULL default '',
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scherk varchar(30) NOT NULL default '',
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favo_boek varchar(50) NOT NULL default '',
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favo_tijdschrift varchar(50) NOT NULL default '',
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favo_tv varchar(50) NOT NULL default '',
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favo_eten varchar(50) NOT NULL default '',
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favo_muziek varchar(30) NOT NULL default '',
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info text NOT NULL default '',
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ipnr varchar(30) NOT NULL default '',
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PRIMARY KEY (member_id)
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) ENGINE=MyISAM PACK_KEYS=1;
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Warnings:
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Warning 1101 BLOB/TEXT column 'info' can't have a default value
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insert into t1 (member_id) values (1),(2),(3);
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select member_id, nickname, voornaam FROM t1
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ORDER by lastchange_datum DESC LIMIT 2;
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member_id nickname voornaam
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1
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2
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drop table t1;
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create table t1 (a int not null, b int, c varchar(10), key (a, b, c));
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insert into t1 values (1, NULL, NULL), (1, NULL, 'b'), (1, 1, NULL), (1, 1, 'b'), (1, 1, 'b'), (2, 1, 'a'), (2, 1, 'b'), (2, 2, 'a'), (2, 2, 'b'), (2, 3, 'c'),(1,3,'b');
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explain select * from t1 where (a = 1 and b is null and c = 'b') or (a > 2) order by a desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index a a 22 NULL 11 Using where; Using index
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select * from t1 where (a = 1 and b is null and c = 'b') or (a > 2) order by a desc;
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a b c
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1 NULL b
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explain select * from t1 where a >= 1 and a < 3 order by a desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range a a 4 NULL 10 Using where; Using index
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select * from t1 where a >= 1 and a < 3 order by a desc;
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a b c
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2 3 c
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2 2 b
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2 2 a
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2 1 b
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2 1 a
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1 3 b
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1 1 b
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1 1 b
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1 1 NULL
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1 NULL b
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1 NULL NULL
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explain select * from t1 where a = 1 order by a desc, b desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref a a 4 const 5 Using where; Using index
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select * from t1 where a = 1 order by a desc, b desc;
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a b c
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1 3 b
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1 1 b
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1 1 b
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1 1 NULL
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1 NULL b
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1 NULL NULL
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explain select * from t1 where a = 1 and b is null order by a desc, b desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref a a 9 const,const 2 Using where; Using index; Using filesort
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select * from t1 where a = 1 and b is null order by a desc, b desc;
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a b c
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1 NULL NULL
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1 NULL b
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explain select * from t1 where a >= 1 and a < 3 and b >0 order by a desc,b desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range a a 9 NULL 8 Using where; Using index
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explain select * from t1 where a = 2 and b >0 order by a desc,b desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range a a 9 NULL 5 Using where; Using index
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explain select * from t1 where a = 2 and b is null order by a desc,b desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref a a 9 const,const 1 Using where; Using index; Using filesort
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explain select * from t1 where a = 2 and (b is null or b > 0) order by a
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desc,b desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range a a 9 NULL 6 Using where; Using index
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explain select * from t1 where a = 2 and b > 0 order by a desc,b desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range a a 9 NULL 5 Using where; Using index
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explain select * from t1 where a = 2 and b < 2 order by a desc,b desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range a a 9 NULL 2 Using where; Using index
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explain select * from t1 where a = 1 order by b desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref a a 4 const 5 Using where; Using index
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select * from t1 where a = 1 order by b desc;
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a b c
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1 3 b
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1 1 b
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1 1 b
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1 1 NULL
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1 NULL b
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1 NULL NULL
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alter table t1 modify b int not null, modify c varchar(10) not null;
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Warnings:
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Warning 1265 Data truncated for column 'b' at row 1
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Warning 1265 Data truncated for column 'c' at row 1
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Warning 1265 Data truncated for column 'b' at row 2
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Warning 1265 Data truncated for column 'c' at row 3
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explain select * from t1 order by a, b, c;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL a 20 NULL 11 Using index
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select * from t1 order by a, b, c;
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a b c
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1 0
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1 0 b
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1 1
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1 1 b
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1 1 b
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1 3 b
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2 1 a
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2 1 b
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2 2 a
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2 2 b
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2 3 c
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explain select * from t1 order by a desc, b desc, c desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL a 20 NULL 11 Using index
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select * from t1 order by a desc, b desc, c desc;
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a b c
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2 3 c
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2 2 b
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2 2 a
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2 1 b
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2 1 a
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1 3 b
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1 1 b
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1 1 b
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1 1
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1 0 b
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1 0
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explain select * from t1 where (a = 1 and b = 1 and c = 'b') or (a > 2) order by a desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range a a 20 NULL 3 Using where; Using index
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select * from t1 where (a = 1 and b = 1 and c = 'b') or (a > 2) order by a desc;
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a b c
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1 1 b
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1 1 b
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explain select * from t1 where a < 2 and b <= 1 order by a desc, b desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range a a 4 NULL 6 Using where; Using index
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select * from t1 where a < 2 and b <= 1 order by a desc, b desc;
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a b c
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1 1 b
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1 1 b
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1 1
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1 0 b
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1 0
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select count(*) from t1 where a < 5 and b > 0;
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count(*)
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9
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select * from t1 where a < 5 and b > 0 order by a desc,b desc;
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a b c
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2 3 c
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2 2 b
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2 2 a
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2 1 b
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2 1 a
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1 3 b
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1 1 b
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1 1 b
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1 1
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explain select * from t1 where a between 1 and 3 and b <= 1 order by a desc, b desc;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range a a 8 NULL 10 Using where; Using index
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|
select * from t1 where a between 1 and 3 and b <= 1 order by a desc, b desc;
|
|
a b c
|
|
2 1 b
|
|
2 1 a
|
|
1 1 b
|
|
1 1 b
|
|
1 1
|
|
1 0 b
|
|
1 0
|
|
explain select * from t1 where a between 0 and 1 order by a desc, b desc;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 range a a 4 NULL 5 Using where; Using index
|
|
select * from t1 where a between 0 and 1 order by a desc, b desc;
|
|
a b c
|
|
1 3 b
|
|
1 1 b
|
|
1 1 b
|
|
1 1
|
|
1 0 b
|
|
1 0
|
|
drop table t1;
|
|
CREATE TABLE t1 (
|
|
gid int(10) unsigned NOT NULL auto_increment,
|
|
cid smallint(5) unsigned NOT NULL default '0',
|
|
PRIMARY KEY (gid),
|
|
KEY component_id (cid)
|
|
) ENGINE=MyISAM;
|
|
INSERT INTO t1 VALUES (103853,108),(103867,108),(103962,108),(104505,108),(104619,108),(104620,108);
|
|
ALTER TABLE t1 add skr int(10) not null;
|
|
CREATE TABLE t2 (
|
|
gid int(10) unsigned NOT NULL default '0',
|
|
uid smallint(5) unsigned NOT NULL default '1',
|
|
sid tinyint(3) unsigned NOT NULL default '1',
|
|
PRIMARY KEY (gid),
|
|
KEY uid (uid),
|
|
KEY status_id (sid)
|
|
) ENGINE=MyISAM;
|
|
INSERT INTO t2 VALUES (103853,250,5),(103867,27,5),(103962,27,5),(104505,117,5),(104619,75,5),(104620,15,5);
|
|
CREATE TABLE t3 (
|
|
uid smallint(6) NOT NULL auto_increment,
|
|
PRIMARY KEY (uid)
|
|
) ENGINE=MyISAM;
|
|
INSERT INTO t3 VALUES (1),(15),(27),(75),(117),(250);
|
|
ALTER TABLE t3 add skr int(10) not null;
|
|
select t1.gid, t2.sid, t3.uid from t2, t1, t3 where t2.gid = t1.gid and t2.uid = t3.uid order by t3.uid, t1.gid;
|
|
gid sid uid
|
|
104620 5 15
|
|
103867 5 27
|
|
103962 5 27
|
|
104619 5 75
|
|
104505 5 117
|
|
103853 5 250
|
|
select t1.gid, t2.sid, t3.uid from t3, t2, t1 where t2.gid = t1.gid and t2.uid = t3.uid order by t3.uid, t1.gid;
|
|
gid sid uid
|
|
104620 5 15
|
|
103867 5 27
|
|
103962 5 27
|
|
104619 5 75
|
|
104505 5 117
|
|
103853 5 250
|
|
EXPLAIN select t1.gid, t2.sid, t3.uid from t3, t2, t1 where t2.gid = t1.gid and t2.uid = t3.uid order by t1.gid, t3.uid;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 ALL PRIMARY,uid NULL NULL NULL 6 Using temporary; Using filesort
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 2 test.t2.uid 1 Using where; Using index
|
|
1 SIMPLE t1 eq_ref PRIMARY PRIMARY 4 test.t2.gid 1 Using index
|
|
EXPLAIN SELECT t1.gid, t3.uid from t1, t3 where t1.gid = t3.uid order by t1.gid,t3.skr;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t3 ALL PRIMARY NULL NULL NULL 6 Using temporary; Using filesort
|
|
1 SIMPLE t1 eq_ref PRIMARY PRIMARY 4 test.t3.uid 1 Using where; Using index
|
|
EXPLAIN SELECT t1.gid, t2.sid, t3.uid from t2, t1, t3 where t2.gid = t1.gid and t2.uid = t3.uid order by t3.uid, t1.gid;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 ALL PRIMARY,uid NULL NULL NULL 6 Using temporary; Using filesort
|
|
1 SIMPLE t1 eq_ref PRIMARY PRIMARY 4 test.t2.gid 1 Using index
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 2 test.t2.uid 1 Using where; Using index
|
|
EXPLAIN SELECT t1.gid, t3.uid from t1, t3 where t1.gid = t3.uid order by t3.skr,t1.gid;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t3 ALL PRIMARY NULL NULL NULL 6 Using temporary; Using filesort
|
|
1 SIMPLE t1 eq_ref PRIMARY PRIMARY 4 test.t3.uid 1 Using where; Using index
|
|
EXPLAIN SELECT t1.gid, t3.uid from t1, t3 where t1.skr = t3.uid order by t1.gid,t3.skr;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 6 Using temporary; Using filesort
|
|
1 SIMPLE t3 eq_ref PRIMARY PRIMARY 2 test.t1.skr 1 Using where
|
|
drop table t1,t2,t3;
|
|
CREATE TABLE t1 (
|
|
`titre` char(80) NOT NULL default '',
|
|
`numeropost` mediumint(8) unsigned NOT NULL auto_increment,
|
|
`date` datetime NOT NULL default '0000-00-00 00:00:00',
|
|
`auteur` char(35) NOT NULL default '',
|
|
`icone` tinyint(2) unsigned NOT NULL default '0',
|
|
`lastauteur` char(35) NOT NULL default '',
|
|
`nbrep` smallint(6) unsigned NOT NULL default '0',
|
|
`dest` char(35) NOT NULL default '',
|
|
`lu` tinyint(1) unsigned NOT NULL default '0',
|
|
`vue` mediumint(8) unsigned NOT NULL default '0',
|
|
`ludest` tinyint(1) unsigned NOT NULL default '0',
|
|
`ouvert` tinyint(1) unsigned NOT NULL default '1',
|
|
PRIMARY KEY (`numeropost`),
|
|
KEY `date` (`date`),
|
|
KEY `dest` (`dest`,`ludest`),
|
|
KEY `auteur` (`auteur`,`lu`),
|
|
KEY `auteur_2` (`auteur`,`date`),
|
|
KEY `dest_2` (`dest`,`date`)
|
|
) CHECKSUM=1;
|
|
CREATE TABLE t2 (
|
|
`numeropost` mediumint(8) unsigned NOT NULL default '0',
|
|
`pseudo` char(35) NOT NULL default '',
|
|
PRIMARY KEY (`numeropost`,`pseudo`),
|
|
KEY `pseudo` (`pseudo`)
|
|
);
|
|
INSERT INTO t1 (titre,auteur,dest) VALUES ('test','joce','bug');
|
|
INSERT INTO t2 (numeropost,pseudo) VALUES (1,'joce'),(1,'bug');
|
|
SELECT titre,t1.numeropost,auteur,icone,nbrep,0,date,vue,ouvert,lastauteur,dest FROM t2 LEFT JOIN t1 USING(numeropost) WHERE t2.pseudo='joce' ORDER BY date DESC LIMIT 0,30;
|
|
titre numeropost auteur icone nbrep 0 date vue ouvert lastauteur dest
|
|
test 1 joce 0 0 0 0000-00-00 00:00:00 0 1 bug
|
|
SELECT titre,numeropost,auteur,icone,nbrep,0,date,vue,ouvert,lastauteur,dest FROM t2 LEFT JOIN t1 USING(numeropost) WHERE t2.pseudo='joce' ORDER BY date DESC LIMIT 0,30;
|
|
titre numeropost auteur icone nbrep 0 date vue ouvert lastauteur dest
|
|
test 1 joce 0 0 0 0000-00-00 00:00:00 0 1 bug
|
|
SELECT titre,t1.numeropost,auteur,icone,nbrep,'0',date,vue,ouvert,lastauteur,dest FROM t2 LEFT JOIN t1 USING(numeropost) WHERE t2.pseudo='joce' ORDER BY date DESC LIMIT 0,30;
|
|
titre numeropost auteur icone nbrep 0 date vue ouvert lastauteur dest
|
|
test 1 joce 0 0 0 0000-00-00 00:00:00 0 1 bug
|
|
SELECT titre,numeropost,auteur,icone,nbrep,'0',date,vue,ouvert,lastauteur,dest FROM t2 LEFT JOIN t1 USING(numeropost) WHERE t2.pseudo='joce' ORDER BY date DESC LIMIT 0,30;
|
|
titre numeropost auteur icone nbrep 0 date vue ouvert lastauteur dest
|
|
test 1 joce 0 0 0 0000-00-00 00:00:00 0 1 bug
|
|
drop table t1,t2;
|
|
CREATE TABLE t1 (a int, b int);
|
|
INSERT INTO t1 VALUES (1, 2);
|
|
INSERT INTO t1 VALUES (3, 4);
|
|
INSERT INTO t1 VALUES (5, NULL);
|
|
SELECT * FROM t1 ORDER BY b;
|
|
a b
|
|
5 NULL
|
|
1 2
|
|
3 4
|
|
SELECT * FROM t1 ORDER BY b DESC;
|
|
a b
|
|
3 4
|
|
1 2
|
|
5 NULL
|
|
SELECT * FROM t1 ORDER BY (a + b);
|
|
a b
|
|
5 NULL
|
|
1 2
|
|
3 4
|
|
SELECT * FROM t1 ORDER BY (a + b) DESC;
|
|
a b
|
|
3 4
|
|
1 2
|
|
5 NULL
|
|
DROP TABLE t1;
|
|
create table t1(id int not null auto_increment primary key, t char(12));
|
|
explain select id,t from t1 order by id;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 1000 Using filesort
|
|
explain select id,t from t1 force index (primary) order by id;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL PRIMARY 4 NULL 1000
|
|
drop table t1;
|
|
CREATE TABLE t1 (
|
|
FieldKey varchar(36) NOT NULL default '',
|
|
LongVal bigint(20) default NULL,
|
|
StringVal mediumtext,
|
|
KEY FieldKey (FieldKey),
|
|
KEY LongField (FieldKey,LongVal),
|
|
KEY StringField (FieldKey,StringVal(32))
|
|
);
|
|
INSERT INTO t1 VALUES ('0',3,'0'),('0',2,'1'),('0',1,'2'),('1',2,'1'),('1',1,'3'), ('1',0,'2'),('2',3,'0'),('2',2,'1'),('2',1,'2'),('2',3,'0'),('2',2,'1'),('2',1,'2'),('3',2,'1'),('3',1,'2'),('3','3','3');
|
|
EXPLAIN SELECT * FROM t1 WHERE FieldKey = '1' ORDER BY LongVal;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ref FieldKey,LongField,StringField LongField 38 const 3 Using where
|
|
SELECT * FROM t1 WHERE FieldKey = '1' ORDER BY LongVal;
|
|
FieldKey LongVal StringVal
|
|
1 0 2
|
|
1 1 3
|
|
1 2 1
|
|
EXPLAIN SELECT * FROM t1 WHERE FieldKey > '2' ORDER BY LongVal;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 range FieldKey,LongField,StringField FieldKey 38 NULL 4 Using where; Using filesort
|
|
SELECT * FROM t1 WHERE FieldKey > '2' ORDER BY LongVal;
|
|
FieldKey LongVal StringVal
|
|
3 1 2
|
|
3 2 1
|
|
3 3 3
|
|
EXPLAIN SELECT * FROM t1 WHERE FieldKey > '2' ORDER BY FieldKey, LongVal;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 range FieldKey,LongField,StringField LongField 38 NULL 4 Using where
|
|
SELECT * FROM t1 WHERE FieldKey > '2' ORDER BY FieldKey, LongVal;
|
|
FieldKey LongVal StringVal
|
|
3 1 2
|
|
3 2 1
|
|
3 3 3
|
|
DROP TABLE t1;
|
|
CREATE TABLE t1 (a INT, b INT);
|
|
SET @id=0;
|
|
UPDATE t1 SET a=0 ORDER BY (a=@id), b;
|
|
DROP TABLE t1;
|
|
CREATE TABLE t1 ( id smallint(6) unsigned NOT NULL default '0', menu tinyint(4) NOT NULL default '0', KEY id (id), KEY menu (menu)) ENGINE=MyISAM;
|
|
INSERT INTO t1 VALUES (11384, 2),(11392, 2);
|
|
SELECT id FROM t1 WHERE id <11984 AND menu =2 ORDER BY id DESC LIMIT 1 ;
|
|
id
|
|
11392
|
|
drop table t1;
|
|
create table t1(a int, b int, index(b));
|
|
insert into t1 values (2, 1), (1, 1), (4, NULL), (3, NULL), (6, 2), (5, 2);
|
|
explain select * from t1 where b=1 or b is null order by a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ref_or_null b b 5 const 3 Using where; Using filesort
|
|
select * from t1 where b=1 or b is null order by a;
|
|
a b
|
|
1 1
|
|
2 1
|
|
3 NULL
|
|
4 NULL
|
|
explain select * from t1 where b=2 or b is null order by a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ref_or_null b b 5 const 4 Using where; Using filesort
|
|
select * from t1 where b=2 or b is null order by a;
|
|
a b
|
|
3 NULL
|
|
4 NULL
|
|
5 2
|
|
6 2
|
|
drop table t1;
|
|
create table t1 (a int not null auto_increment, b int not null, c int not null, d int not null,
|
|
key(a,b,d), key(c,b,a));
|
|
create table t2 like t1;
|
|
insert into t1 values (NULL, 1, 2, 0), (NULL, 2, 1, 1), (NULL, 3, 4, 2), (NULL, 4, 3, 3);
|
|
insert into t2 select null, b, c, d from t1;
|
|
insert into t1 select null, b, c, d from t2;
|
|
insert into t2 select null, b, c, d from t1;
|
|
insert into t1 select null, b, c, d from t2;
|
|
insert into t2 select null, b, c, d from t1;
|
|
insert into t1 select null, b, c, d from t2;
|
|
insert into t2 select null, b, c, d from t1;
|
|
insert into t1 select null, b, c, d from t2;
|
|
insert into t2 select null, b, c, d from t1;
|
|
insert into t1 select null, b, c, d from t2;
|
|
optimize table t1;
|
|
Table Op Msg_type Msg_text
|
|
test.t1 optimize status OK
|
|
set @row=10;
|
|
insert into t1 select 1, b, c + (@row:=@row - 1) * 10, d - @row from t2 limit 10;
|
|
select * from t1 where a=1 and b in (1) order by c, b, a;
|
|
a b c d
|
|
1 1 2 0
|
|
1 1 12 -1
|
|
1 1 52 -5
|
|
1 1 92 -9
|
|
select * from t1 where a=1 and b in (1);
|
|
a b c d
|
|
1 1 92 -9
|
|
1 1 52 -5
|
|
1 1 12 -1
|
|
1 1 2 0
|
|
drop table t1, t2;
|
|
create table t1 (col1 int, col int);
|
|
create table t2 (col2 int, col int);
|
|
insert into t1 values (1,1),(2,2),(3,3);
|
|
insert into t2 values (1,3),(2,2),(3,1);
|
|
select t1.* , t2.col as t2_col from t1 left join t2 on (t1.col1=t2.col2)
|
|
order by col;
|
|
col1 col t2_col
|
|
1 1 3
|
|
2 2 2
|
|
3 3 1
|
|
select col1 as col, col from t1 order by col;
|
|
ERROR 23000: Column 'col' in order clause is ambiguous
|
|
select t1.col as c1, t2.col as c2 from t1, t2 where t1.col1=t2.col2
|
|
order by col;
|
|
ERROR 23000: Column 'col' in order clause is ambiguous
|
|
select t1.col as c1, t2.col as c2 from t1, t2 where t1.col1=t2.col2
|
|
order by col;
|
|
ERROR 23000: Column 'col' in order clause is ambiguous
|
|
select col1 from t1, t2 where t1.col1=t2.col2 order by col;
|
|
ERROR 23000: Column 'col' in order clause is ambiguous
|
|
select t1.col as t1_col, t2.col2 from t1, t2 where t1.col1=t2.col2
|
|
order by col;
|
|
ERROR 23000: Column 'col' in order clause is ambiguous
|
|
select t1.col as t1_col, t2.col from t1, t2 where t1.col1=t2.col2
|
|
order by col;
|
|
t1_col col
|
|
3 1
|
|
2 2
|
|
1 3
|
|
select col2 as c, col as c from t2 order by col;
|
|
c c
|
|
3 1
|
|
2 2
|
|
1 3
|
|
select col2 as col, col as col2 from t2 order by col;
|
|
col col2
|
|
1 3
|
|
2 2
|
|
3 1
|
|
select t2.col2, t2.col, t2.col from t2 order by col;
|
|
col2 col col
|
|
3 1 1
|
|
2 2 2
|
|
1 3 3
|
|
select t2.col2 as col from t2 order by t2.col;
|
|
col
|
|
3
|
|
2
|
|
1
|
|
select t2.col2 as col, t2.col from t2 order by t2.col;
|
|
col col
|
|
3 1
|
|
2 2
|
|
1 3
|
|
select t2.col2, t2.col, t2.col from t2 order by t2.col;
|
|
col2 col col
|
|
3 1 1
|
|
2 2 2
|
|
1 3 3
|
|
drop table t1, t2;
|
|
create table t1 (a char(25));
|
|
insert into t1 set a = repeat('x', 20);
|
|
insert into t1 set a = concat(repeat('x', 19), 'z');
|
|
insert into t1 set a = concat(repeat('x', 19), 'ab');
|
|
insert into t1 set a = concat(repeat('x', 19), 'aa');
|
|
set max_sort_length=20;
|
|
select a from t1 order by a;
|
|
a
|
|
xxxxxxxxxxxxxxxxxxxab
|
|
xxxxxxxxxxxxxxxxxxxaa
|
|
xxxxxxxxxxxxxxxxxxxx
|
|
xxxxxxxxxxxxxxxxxxxz
|
|
drop table t1;
|
|
create table t1 (
|
|
`sid` decimal(8,0) default null,
|
|
`wnid` varchar(11) not null default '',
|
|
key `wnid14` (`wnid`(4)),
|
|
key `wnid` (`wnid`)
|
|
) engine=myisam default charset=latin1;
|
|
insert into t1 (`sid`, `wnid`) values
|
|
('10100','01019000000'),('37986','01019000000'),('37987','01019010000'),
|
|
('39560','01019090000'),('37989','01019000000'),('37990','01019011000'),
|
|
('37991','01019011000'),('37992','01019019000'),('37993','01019030000'),
|
|
('37994','01019090000'),('475','02070000000'),('25253','02071100000'),
|
|
('25255','02071100000'),('25256','02071110000'),('25258','02071130000'),
|
|
('25259','02071190000'),('25260','02071200000'),('25261','02071210000'),
|
|
('25262','02071290000'),('25263','02071300000'),('25264','02071310000'),
|
|
('25265','02071310000'),('25266','02071320000'),('25267','02071320000'),
|
|
('25269','02071330000'),('25270','02071340000'),('25271','02071350000'),
|
|
('25272','02071360000'),('25273','02071370000'),('25281','02071391000'),
|
|
('25282','02071391000'),('25283','02071399000'),('25284','02071400000'),
|
|
('25285','02071410000'),('25286','02071410000'),('25287','02071420000'),
|
|
('25288','02071420000'),('25291','02071430000'),('25290','02071440000'),
|
|
('25292','02071450000'),('25293','02071460000'),('25294','02071470000'),
|
|
('25295','02071491000'),('25296','02071491000'),('25297','02071499000');
|
|
explain select * from t1 where wnid like '0101%' order by wnid;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 range wnid14,wnid wnid 13 NULL 10 Using where
|
|
select * from t1 where wnid like '0101%' order by wnid;
|
|
sid wnid
|
|
10100 01019000000
|
|
37986 01019000000
|
|
37989 01019000000
|
|
37987 01019010000
|
|
37990 01019011000
|
|
37991 01019011000
|
|
37992 01019019000
|
|
37993 01019030000
|
|
39560 01019090000
|
|
37994 01019090000
|
|
drop table t1;
|
|
CREATE TABLE t1 (a int);
|
|
INSERT INTO t1 VALUES (2), (1), (1), (2), (1);
|
|
SELECT a FROM t1 ORDER BY a;
|
|
a
|
|
1
|
|
1
|
|
1
|
|
2
|
|
2
|
|
(SELECT a FROM t1) ORDER BY a;
|
|
a
|
|
1
|
|
1
|
|
1
|
|
2
|
|
2
|
|
DROP TABLE t1;
|
|
CREATE TABLE t1 (a int, b int);
|
|
INSERT INTO t1 VALUES (1,30), (2,20), (1,10), (2,30), (1,20), (2,10);
|
|
(SELECT b,a FROM t1 ORDER BY a,b) ORDER BY b,a;
|
|
b a
|
|
10 1
|
|
10 2
|
|
20 1
|
|
20 2
|
|
30 1
|
|
30 2
|
|
(SELECT b FROM t1 ORDER BY b DESC) ORDER BY b ASC;
|
|
b
|
|
10
|
|
10
|
|
20
|
|
20
|
|
30
|
|
30
|
|
(SELECT b,a FROM t1 ORDER BY b,a) ORDER BY a,b;
|
|
b a
|
|
10 1
|
|
20 1
|
|
30 1
|
|
10 2
|
|
20 2
|
|
30 2
|
|
(SELECT b,a FROM t1 ORDER by b,a LIMIT 3) ORDER by a,b;
|
|
b a
|
|
10 1
|
|
20 1
|
|
10 2
|
|
DROP TABLE t1;
|
|
CREATE TABLE t1 (a INT);
|
|
INSERT INTO t1 VALUES (1),(2);
|
|
SELECT a + 1 AS num FROM t1 ORDER BY 30 - num;
|
|
num
|
|
3
|
|
2
|
|
SELECT CONCAT('test', a) AS str FROM t1 ORDER BY UPPER(str);
|
|
str
|
|
test1
|
|
test2
|
|
SELECT a + 1 AS num FROM t1 GROUP BY 30 - num;
|
|
num
|
|
3
|
|
2
|
|
SELECT a + 1 AS num FROM t1 HAVING 30 - num;
|
|
num
|
|
2
|
|
3
|
|
SELECT a + 1 AS num, num + 1 FROM t1;
|
|
ERROR 42S22: Unknown column 'num' in 'field list'
|
|
SELECT a + 1 AS num, (select num + 2 FROM t1 LIMIT 1) FROM t1;
|
|
num (select num + 2 FROM t1 LIMIT 1)
|
|
2 4
|
|
3 5
|
|
SELECT a.a + 1 AS num FROM t1 a JOIN t1 b ON num = b.a;
|
|
ERROR 42S22: Unknown column 'num' in 'on clause'
|
|
DROP TABLE t1;
|
|
CREATE TABLE bug25126 (
|
|
val int unsigned NOT NULL AUTO_INCREMENT PRIMARY KEY
|
|
);
|
|
UPDATE bug25126 SET MissingCol = MissingCol;
|
|
ERROR 42S22: Unknown column 'MissingCol' in 'field list'
|
|
UPDATE bug25126 SET val = val ORDER BY MissingCol;
|
|
ERROR 42S22: Unknown column 'MissingCol' in 'order clause'
|
|
UPDATE bug25126 SET val = val ORDER BY val;
|
|
UPDATE bug25126 SET val = 1 ORDER BY val;
|
|
UPDATE bug25126 SET val = 1 ORDER BY MissingCol;
|
|
ERROR 42S22: Unknown column 'MissingCol' in 'order clause'
|
|
UPDATE bug25126 SET val = 1 ORDER BY val, MissingCol;
|
|
ERROR 42S22: Unknown column 'MissingCol' in 'order clause'
|
|
UPDATE bug25126 SET val = MissingCol ORDER BY MissingCol;
|
|
ERROR 42S22: Unknown column 'MissingCol' in 'order clause'
|
|
UPDATE bug25126 SET MissingCol = 1 ORDER BY val, MissingCol;
|
|
ERROR 42S22: Unknown column 'MissingCol' in 'order clause'
|
|
UPDATE bug25126 SET MissingCol = 1 ORDER BY MissingCol;
|
|
ERROR 42S22: Unknown column 'MissingCol' in 'order clause'
|
|
UPDATE bug25126 SET MissingCol = val ORDER BY MissingCol;
|
|
ERROR 42S22: Unknown column 'MissingCol' in 'order clause'
|
|
UPDATE bug25126 SET MissingCol = MissingCol ORDER BY MissingCol;
|
|
ERROR 42S22: Unknown column 'MissingCol' in 'order clause'
|
|
DROP TABLE bug25126;
|
|
CREATE TABLE t1 (a int);
|
|
SELECT p.a AS val, q.a AS val1 FROM t1 p, t1 q ORDER BY val > 1;
|
|
val val1
|
|
SELECT p.a AS val, q.a AS val FROM t1 p, t1 q ORDER BY val;
|
|
ERROR 23000: Column 'val' in order clause is ambiguous
|
|
SELECT p.a AS val, q.a AS val FROM t1 p, t1 q ORDER BY val > 1;
|
|
ERROR 23000: Column 'val' in order clause is ambiguous
|
|
DROP TABLE t1;
|
|
CREATE TABLE t1 (a int);
|
|
INSERT INTO t1 VALUES (3), (2), (4), (1);
|
|
SELECT a, IF(a IN (2,3), a, a+10) FROM t1
|
|
ORDER BY IF(a IN (2,3), a, a+10);
|
|
a IF(a IN (2,3), a, a+10)
|
|
2 2
|
|
3 3
|
|
1 11
|
|
4 14
|
|
SELECT a, IF(a NOT IN (2,3), a, a+10) FROM t1
|
|
ORDER BY IF(a NOT IN (2,3), a, a+10);
|
|
a IF(a NOT IN (2,3), a, a+10)
|
|
1 1
|
|
4 4
|
|
2 12
|
|
3 13
|
|
SELECT a, IF(a IN (2,3), a, a+10) FROM t1
|
|
ORDER BY IF(a NOT IN (2,3), a, a+10);
|
|
a IF(a IN (2,3), a, a+10)
|
|
1 11
|
|
4 14
|
|
2 2
|
|
3 3
|
|
SELECT a, IF(a BETWEEN 2 AND 3, a, a+10) FROM t1
|
|
ORDER BY IF(a BETWEEN 2 AND 3, a, a+10);
|
|
a IF(a BETWEEN 2 AND 3, a, a+10)
|
|
2 2
|
|
3 3
|
|
1 11
|
|
4 14
|
|
SELECT a, IF(a NOT BETWEEN 2 AND 3, a, a+10) FROM t1
|
|
ORDER BY IF(a NOT BETWEEN 2 AND 3, a, a+10);
|
|
a IF(a NOT BETWEEN 2 AND 3, a, a+10)
|
|
1 1
|
|
4 4
|
|
2 12
|
|
3 13
|
|
SELECT a, IF(a BETWEEN 2 AND 3, a, a+10) FROM t1
|
|
ORDER BY IF(a NOT BETWEEN 2 AND 3, a, a+10);
|
|
a IF(a BETWEEN 2 AND 3, a, a+10)
|
|
1 11
|
|
4 14
|
|
2 2
|
|
3 3
|
|
SELECT IF(a IN (1,2), a, '') as x1, IF(a NOT IN (1,2), a, '') as x2
|
|
FROM t1 GROUP BY x1, x2;
|
|
x1 x2
|
|
3
|
|
4
|
|
1
|
|
2
|
|
SELECT IF(a IN (1,2), a, '') as x1, IF(a NOT IN (1,2), a, '') as x2
|
|
FROM t1 GROUP BY x1, IF(a NOT IN (1,2), a, '');
|
|
x1 x2
|
|
3
|
|
4
|
|
1
|
|
2
|
|
SELECT a, a IN (1,2) FROM t1 ORDER BY a IN (1,2);
|
|
a a IN (1,2)
|
|
3 0
|
|
4 0
|
|
2 1
|
|
1 1
|
|
SELECT a FROM t1 ORDER BY a IN (1,2);
|
|
a
|
|
3
|
|
4
|
|
2
|
|
1
|
|
SELECT a+10 FROM t1 ORDER BY a IN (1,2);
|
|
a+10
|
|
13
|
|
14
|
|
12
|
|
11
|
|
SELECT a, IF(a IN (1,2), a, a+10) FROM t1
|
|
ORDER BY IF(a IN (3,4), a, a+10);
|
|
a IF(a IN (1,2), a, a+10)
|
|
3 13
|
|
4 14
|
|
1 1
|
|
2 2
|
|
DROP TABLE t1;
|
|
create table t1 (a int not null, b int not null, c int not null);
|
|
insert t1 values (1,1,1),(1,1,2),(1,2,1);
|
|
select a, b from t1 group by a, b order by sum(c);
|
|
a b
|
|
1 2
|
|
1 1
|
|
drop table t1;
|
|
CREATE TABLE t1 (a int, b int, PRIMARY KEY (a));
|
|
INSERT INTO t1 VALUES (1,1), (2,2), (3,3);
|
|
explain SELECT t1.b as a, t2.b as c FROM
|
|
t1 LEFT JOIN t1 t2 ON (t1.a = t2.a AND t2.a = 2)
|
|
ORDER BY c;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 3 Using temporary; Using filesort
|
|
1 SIMPLE t2 const PRIMARY PRIMARY 4 const 1
|
|
SELECT t2.b as c FROM
|
|
t1 LEFT JOIN t1 t2 ON (t1.a = t2.a AND t2.a = 2)
|
|
ORDER BY c;
|
|
c
|
|
NULL
|
|
NULL
|
|
2
|
|
explain SELECT t1.b as a, t2.b as c FROM
|
|
t1 JOIN t1 t2 ON (t1.a = t2.a AND t2.a = 2)
|
|
ORDER BY c;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 const PRIMARY PRIMARY 4 const 1
|
|
1 SIMPLE t2 const PRIMARY PRIMARY 4 const 1
|
|
CREATE TABLE t2 LIKE t1;
|
|
INSERT INTO t2 SELECT * from t1;
|
|
CREATE TABLE t3 LIKE t1;
|
|
INSERT INTO t3 SELECT * from t1;
|
|
CREATE TABLE t4 LIKE t1;
|
|
INSERT INTO t4 SELECT * from t1;
|
|
INSERT INTO t1 values (0,0),(4,4);
|
|
SELECT t2.b FROM t1 LEFT JOIN (t2, t3 LEFT JOIN t4 ON t3.a=t4.a)
|
|
ON (t1.a=t2.a AND t1.b=t3.b) order by t2.b;
|
|
b
|
|
NULL
|
|
NULL
|
|
1
|
|
2
|
|
3
|
|
DROP TABLE t1,t2,t3,t4;
|
|
create table t1 (a int, b int, c int);
|
|
insert into t1 values (1,2,3), (9,8,3), (19,4,3), (1,4,9);
|
|
select a,(sum(b)/sum(c)) as ratio from t1 group by a order by sum(b)/sum(c) asc;
|
|
a ratio
|
|
1 0.5000
|
|
19 1.3333
|
|
9 2.6667
|
|
drop table t1;
|
|
CREATE TABLE t1 (a INT UNSIGNED NOT NULL, b TIME);
|
|
INSERT INTO t1 (a) VALUES (100000), (0), (100), (1000000),(10000), (1000), (10);
|
|
UPDATE t1 SET b = SEC_TO_TIME(a);
|
|
SELECT a, b FROM t1 ORDER BY b DESC;
|
|
a b
|
|
1000000 277:46:40
|
|
100000 27:46:40
|
|
10000 02:46:40
|
|
1000 00:16:40
|
|
100 00:01:40
|
|
10 00:00:10
|
|
0 00:00:00
|
|
SELECT a, b FROM t1 ORDER BY SEC_TO_TIME(a) DESC;
|
|
a b
|
|
1000000 277:46:40
|
|
100000 27:46:40
|
|
10000 02:46:40
|
|
1000 00:16:40
|
|
100 00:01:40
|
|
10 00:00:10
|
|
0 00:00:00
|
|
DROP TABLE t1;
|
|
CREATE TABLE t1 (a INT, b INT, PRIMARY KEY (a), UNIQUE KEY b (b));
|
|
INSERT INTO t1 VALUES (1,1),(2,2);
|
|
CREATE TABLE t2 (a INT, b INT, KEY a (a,b));
|
|
INSERT INTO t2 VALUES (1,1),(1,2),(2,1),(2,2);
|
|
EXPLAIN SELECT 1 FROM t1,t2 WHERE t1.b=2 AND t1.a=t2.a ORDER BY t2.b;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 const PRIMARY,b b 5 const 1
|
|
1 SIMPLE t2 ref a a 5 const 2 Using where; Using index
|
|
DROP TABLE t1,t2;
|
|
CREATE TABLE t1(
|
|
id int auto_increment PRIMARY KEY, c2 int, c3 int, INDEX k2(c2), INDEX k3(c3));
|
|
INSERT INTO t1 (c2,c3) VALUES
|
|
(31,34),(35,38),(34,31),(32,35),(31,39),
|
|
(11,14),(15,18),(14,11),(12,15),(11,19);
|
|
INSERT INTO t1 (c2,c3) SELECT c2,c3 FROM t1;
|
|
INSERT INTO t1 (c2,c3) SELECT c2,c3 FROM t1;
|
|
INSERT INTO t1 (c2,c3) SELECT c2,c3 FROM t1;
|
|
INSERT INTO t1 (c2,c3) SELECT c2,c3 FROM t1;
|
|
INSERT INTO t1 (c2,c3) SELECT c2,c3 FROM t1;
|
|
INSERT INTO t1 (c2,c3) SELECT c2,c3 FROM t1;
|
|
INSERT INTO t1 (c2,c3) SELECT c2,c3 FROM t1;
|
|
INSERT INTO t1 (c2,c3) SELECT c2,c3 FROM t1;
|
|
INSERT INTO t1 (c2,c3) SELECT c2,c3 FROM t1;
|
|
INSERT INTO t1 (c2,c3) SELECT c2,c3 FROM t1;
|
|
INSERT INTO t1 (c2,c3) SELECT c2,c3 FROM t1;
|
|
INSERT INTO t1 (c2,c3) SELECT c2,c3 FROM t1;
|
|
UPDATE t1 SET c2=20 WHERE id%100 = 0;
|
|
SELECT COUNT(*) FROM t1;
|
|
COUNT(*)
|
|
40960
|
|
CREATE TABLE t2 LIKE t1;
|
|
INSERT INTO t2 SELECT * FROM t1 ORDER BY id;
|
|
EXPLAIN SELECT id,c3 FROM t2 WHERE c2=11 ORDER BY c3 LIMIT 20;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 index k2 k3 5 NULL 111 Using where
|
|
EXPLAIN SELECT id,c3 FROM t2 WHERE c2=11 ORDER BY c3 LIMIT 4000;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 ref k2 k2 5 const 7341 Using where; Using filesort
|
|
EXPLAIN SELECT id,c3 FROM t2 WHERE c2 BETWEEN 10 AND 12 ORDER BY c3 LIMIT 20;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 index k2 k3 5 NULL 73 Using where
|
|
EXPLAIN SELECT id,c3 FROM t2 WHERE c2 BETWEEN 20 AND 30 ORDER BY c3 LIMIT 4000;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 range k2 k2 5 NULL 386 Using where; Using filesort
|
|
SELECT id,c3 FROM t2 WHERE c2=11 ORDER BY c3 LIMIT 20;
|
|
id c3
|
|
6 14
|
|
16 14
|
|
26 14
|
|
36 14
|
|
46 14
|
|
56 14
|
|
66 14
|
|
76 14
|
|
86 14
|
|
96 14
|
|
106 14
|
|
116 14
|
|
126 14
|
|
136 14
|
|
146 14
|
|
156 14
|
|
166 14
|
|
176 14
|
|
186 14
|
|
196 14
|
|
DROP TABLE t1,t2;
|
|
CREATE TABLE t1 (
|
|
a INT,
|
|
b INT,
|
|
PRIMARY KEY (a),
|
|
KEY ab(a, b)
|
|
);
|
|
INSERT INTO t1 VALUES (1,1),(2,2),(3,3),(4,4);
|
|
INSERT INTO t1 SELECT a + 4, b + 4 FROM t1;
|
|
INSERT INTO t1 SELECT a + 8, b + 8 FROM t1;
|
|
INSERT INTO t1 SELECT a +16, b +16 FROM t1;
|
|
INSERT INTO t1 SELECT a +32, b +32 FROM t1;
|
|
INSERT INTO t1 SELECT a +64, b +64 FROM t1;
|
|
EXPLAIN SELECT a FROM t1 IGNORE INDEX FOR GROUP BY (a, ab) GROUP BY a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 range NULL ab 4 NULL 10 Using index for group-by
|
|
SELECT a FROM t1 IGNORE INDEX FOR GROUP BY (a, ab) GROUP BY a;
|
|
a
|
|
1
|
|
2
|
|
3
|
|
4
|
|
5
|
|
6
|
|
7
|
|
8
|
|
9
|
|
10
|
|
11
|
|
12
|
|
13
|
|
14
|
|
15
|
|
16
|
|
17
|
|
18
|
|
19
|
|
20
|
|
21
|
|
22
|
|
23
|
|
24
|
|
25
|
|
26
|
|
27
|
|
28
|
|
29
|
|
30
|
|
31
|
|
32
|
|
33
|
|
34
|
|
35
|
|
36
|
|
37
|
|
38
|
|
39
|
|
40
|
|
41
|
|
42
|
|
43
|
|
44
|
|
45
|
|
46
|
|
47
|
|
48
|
|
49
|
|
50
|
|
51
|
|
52
|
|
53
|
|
54
|
|
55
|
|
56
|
|
57
|
|
58
|
|
59
|
|
60
|
|
61
|
|
62
|
|
63
|
|
64
|
|
65
|
|
66
|
|
67
|
|
68
|
|
69
|
|
70
|
|
71
|
|
72
|
|
73
|
|
74
|
|
75
|
|
76
|
|
77
|
|
78
|
|
79
|
|
80
|
|
81
|
|
82
|
|
83
|
|
84
|
|
85
|
|
86
|
|
87
|
|
88
|
|
89
|
|
90
|
|
91
|
|
92
|
|
93
|
|
94
|
|
95
|
|
96
|
|
97
|
|
98
|
|
99
|
|
100
|
|
101
|
|
102
|
|
103
|
|
104
|
|
105
|
|
106
|
|
107
|
|
108
|
|
109
|
|
110
|
|
111
|
|
112
|
|
113
|
|
114
|
|
115
|
|
116
|
|
117
|
|
118
|
|
119
|
|
120
|
|
121
|
|
122
|
|
123
|
|
124
|
|
125
|
|
126
|
|
127
|
|
128
|
|
SELECT @tmp_tables_after = @tmp_tables_before ;
|
|
@tmp_tables_after = @tmp_tables_before
|
|
1
|
|
EXPLAIN SELECT a FROM t1 IGNORE INDEX FOR ORDER BY (a, ab) ORDER BY a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL PRIMARY 4 NULL 128 Using index
|
|
SELECT a FROM t1 IGNORE INDEX FOR ORDER BY (a, ab) ORDER BY a;
|
|
a
|
|
1
|
|
2
|
|
3
|
|
4
|
|
5
|
|
6
|
|
7
|
|
8
|
|
9
|
|
10
|
|
11
|
|
12
|
|
13
|
|
14
|
|
15
|
|
16
|
|
17
|
|
18
|
|
19
|
|
20
|
|
21
|
|
22
|
|
23
|
|
24
|
|
25
|
|
26
|
|
27
|
|
28
|
|
29
|
|
30
|
|
31
|
|
32
|
|
33
|
|
34
|
|
35
|
|
36
|
|
37
|
|
38
|
|
39
|
|
40
|
|
41
|
|
42
|
|
43
|
|
44
|
|
45
|
|
46
|
|
47
|
|
48
|
|
49
|
|
50
|
|
51
|
|
52
|
|
53
|
|
54
|
|
55
|
|
56
|
|
57
|
|
58
|
|
59
|
|
60
|
|
61
|
|
62
|
|
63
|
|
64
|
|
65
|
|
66
|
|
67
|
|
68
|
|
69
|
|
70
|
|
71
|
|
72
|
|
73
|
|
74
|
|
75
|
|
76
|
|
77
|
|
78
|
|
79
|
|
80
|
|
81
|
|
82
|
|
83
|
|
84
|
|
85
|
|
86
|
|
87
|
|
88
|
|
89
|
|
90
|
|
91
|
|
92
|
|
93
|
|
94
|
|
95
|
|
96
|
|
97
|
|
98
|
|
99
|
|
100
|
|
101
|
|
102
|
|
103
|
|
104
|
|
105
|
|
106
|
|
107
|
|
108
|
|
109
|
|
110
|
|
111
|
|
112
|
|
113
|
|
114
|
|
115
|
|
116
|
|
117
|
|
118
|
|
119
|
|
120
|
|
121
|
|
122
|
|
123
|
|
124
|
|
125
|
|
126
|
|
127
|
|
128
|
|
SELECT @tmp_tables_after = @tmp_tables_before;
|
|
@tmp_tables_after = @tmp_tables_before
|
|
1
|
|
DROP TABLE t1;
|
|
#
|
|
# Bug#31590: Wrong error message on sort buffer being too small.
|
|
#
|
|
create table t1(a int, b tinytext);
|
|
insert into t1 values (1,2),(3,2);
|
|
set session sort_buffer_size= 30000;
|
|
Warnings:
|
|
Warning 1292 Truncated incorrect sort_buffer_size value: '30000'
|
|
set session max_sort_length= 2180;
|
|
select * from t1 order by b;
|
|
ERROR HY001: Out of sort memory; increase server sort buffer size
|
|
drop table t1;
|
|
#
|
|
# Bug #39844: Query Crash Mysql Server 5.0.67
|
|
#
|
|
CREATE TABLE t1 (a INT PRIMARY KEY);
|
|
CREATE TABLE t2 (a INT PRIMARY KEY, b INT);
|
|
CREATE TABLE t3 (c INT);
|
|
INSERT INTO t1 (a) VALUES (1), (2);
|
|
INSERT INTO t2 (a,b) VALUES (1,2), (2,3);
|
|
INSERT INTO t3 (c) VALUES (1), (2);
|
|
SELECT
|
|
(SELECT t1.a FROM t1, t2 WHERE t1.a = t2.b AND t2.a = t3.c ORDER BY t1.a)
|
|
FROM t3;
|
|
(SELECT t1.a FROM t1, t2 WHERE t1.a = t2.b AND t2.a = t3.c ORDER BY t1.a)
|
|
2
|
|
NULL
|
|
DROP TABLE t1, t2, t3;
|
|
#
|
|
# Bug #42760: Select doesn't return desired results when we have null
|
|
# values
|
|
#
|
|
CREATE TABLE t1 (
|
|
a INT,
|
|
c INT,
|
|
UNIQUE KEY a_c (a,c),
|
|
KEY (a));
|
|
INSERT INTO t1 VALUES (1, 10), (2, NULL);
|
|
# Must use ref-or-null on the a_c index
|
|
EXPLAIN
|
|
SELECT 1 AS col FROM t1 WHERE a=2 AND (c=10 OR c IS NULL) ORDER BY c;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ref_or_null a_c,a a_c 10 const,const 1 Using where
|
|
# Must return 1 row
|
|
SELECT 1 AS col FROM t1 WHERE a=2 AND (c=10 OR c IS NULL) ORDER BY c;
|
|
col
|
|
1
|
|
# Must use ref-or-null on the a_c index
|
|
EXPLAIN
|
|
SELECT 1 AS col FROM t1 WHERE a=2 AND (c=10 OR c IS NULL) ORDER BY c DESC;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
x x x ref_or_null a_c,a x x x x x
|
|
# Must return 1 row
|
|
SELECT 1 AS col FROM t1 WHERE a=2 AND (c=10 OR c IS NULL) ORDER BY c DESC;
|
|
col
|
|
1
|
|
DROP TABLE t1;
|
|
End of 5.0 tests
|
|
CREATE TABLE t2 (a varchar(32), b int(11), c float, d double,
|
|
UNIQUE KEY a (a,b,c), KEY b (b), KEY c (c));
|
|
CREATE TABLE t1 (a varchar(32), b char(3), UNIQUE KEY a (a,b), KEY b (b));
|
|
CREATE TABLE t3 (a varchar(32), b char(3), UNIQUE KEY a (a,b));
|
|
INSERT INTO t3 SELECT * FROM t1;
|
|
EXPLAIN
|
|
SELECT d FROM t1, t2
|
|
WHERE t2.b=14 AND t2.a=t1.a AND 5.1<t2.c AND t1.b='DE'
|
|
ORDER BY t2.c LIMIT 1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ref a,b b 4 const 4 Using where; Using temporary; Using filesort
|
|
1 SIMPLE t2 ref a,b,c a 40 test.t1.a,const 11 Using where
|
|
SELECT d FROM t1, t2
|
|
WHERE t2.b=14 AND t2.a=t1.a AND 5.1<t2.c AND t1.b='DE'
|
|
ORDER BY t2.c LIMIT 1;
|
|
d
|
|
52.5
|
|
EXPLAIN
|
|
SELECT d FROM t3 AS t1, t2 AS t2
|
|
WHERE t2.b=14 AND t2.a=t1.a AND 5.1<t2.c AND t1.b='DE'
|
|
ORDER BY t2.c LIMIT 1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 range a,b,c c 5 NULL 420 Using where
|
|
1 SIMPLE t1 ref a a 39 test.t2.a,const 10 Using where; Using index
|
|
SELECT d FROM t3 AS t1, t2 AS t2
|
|
WHERE t2.b=14 AND t2.a=t1.a AND 5.1<t2.c AND t1.b='DE'
|
|
ORDER BY t2.c LIMIT 1;
|
|
d
|
|
52.5
|
|
DROP TABLE t1,t2,t3;
|
|
CREATE TABLE t1 (
|
|
id1 INT NULL,
|
|
id2 INT NOT NULL,
|
|
junk INT NOT NULL,
|
|
PRIMARY KEY (id1, id2, junk),
|
|
INDEX id2_j_id1 (id2, junk, id1)
|
|
);
|
|
INSERT INTO t1 VALUES (1, 1, 1), (2, 1, 2), (3, 1, 3), (4, 1, 4);
|
|
INSERT INTO t1 VALUES (5, 2, 1), (6, 2, 2), (7, 2, 3), (8, 2, 4);
|
|
INSERT INTO t1 VALUES (9, 3, 1), (10, 3, 2), (11, 3, 3), (12, 3, 4);
|
|
INSERT INTO t1 VALUES (13, 4, 1), (14, 4, 2), (15, 4, 3), (16, 4, 4);
|
|
INSERT INTO t1 VALUES (17, 5, 1), (18, 5, 2), (19, 5, 3), (20, 5, 4);
|
|
INSERT INTO t1 VALUES (21, 6, 1), (22, 6, 2), (23, 6, 3), (24, 6, 4);
|
|
INSERT INTO t1 VALUES (25, 7, 1), (26, 7, 2), (27, 7, 3), (28, 7, 4);
|
|
INSERT INTO t1 VALUES (29, 8, 1), (30, 8, 2), (31, 8, 3), (32, 8, 4);
|
|
INSERT INTO t1 VALUES (33, 9, 1), (34, 9, 2), (35, 9, 3), (36, 9, 4);
|
|
EXPLAIN SELECT id1 FROM t1 WHERE id2 = 4 ORDER BY id1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ref id2_j_id1 id2_j_id1 4 const 4 Using where; Using index; Using filesort
|
|
SELECT id1 FROM t1 WHERE id2 = 4 ORDER BY id1;
|
|
id1
|
|
13
|
|
14
|
|
15
|
|
16
|
|
DROP TABLE t1;
|
|
CREATE TABLE t1 (
|
|
a INT,
|
|
b INT NOT NULL,
|
|
c char(100),
|
|
KEY (b, c),
|
|
KEY (b, a, c)
|
|
)
|
|
DEFAULT CHARSET = utf8;
|
|
INSERT INTO t1 VALUES
|
|
(1, 1, 1),
|
|
(2, 2, 2),
|
|
(3, 3, 3),
|
|
(4, 4, 4),
|
|
(5, 5, 5),
|
|
(6, 6, 6),
|
|
(7, 7, 7),
|
|
(8, 8, 8),
|
|
(9, 9, 9);
|
|
INSERT INTO t1 SELECT a + 10, b, c FROM t1;
|
|
INSERT INTO t1 SELECT a + 20, b, c FROM t1;
|
|
INSERT INTO t1 SELECT a + 40, b, c FROM t1;
|
|
INSERT INTO t1 SELECT a + 80, b, c FROM t1;
|
|
INSERT INTO t1 SELECT a + 160, b, c FROM t1;
|
|
INSERT INTO t1 SELECT a + 320, b, c FROM t1;
|
|
INSERT INTO t1 SELECT a + 640, b, c FROM t1;
|
|
INSERT INTO t1 SELECT a + 1280, b, c FROM t1 LIMIT 80;
|
|
EXPLAIN
|
|
SELECT a FROM t1 WHERE b = 1 ORDER BY c DESC LIMIT 9;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 range b,b_2 b 4 NULL 226 Using where
|
|
SELECT a FROM t1 WHERE b = 1 ORDER BY c DESC LIMIT 9;
|
|
a
|
|
2071
|
|
2061
|
|
2051
|
|
2041
|
|
2031
|
|
2021
|
|
2011
|
|
2001
|
|
1991
|
|
EXPLAIN
|
|
SELECT DISTINCT a FROM t1 WHERE b = 1 ORDER BY c DESC LIMIT 0, 9;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 range b,b_2 b 4 NULL 226 Using where; Using temporary
|
|
SELECT DISTINCT a FROM t1 WHERE b = 1 ORDER BY c DESC LIMIT 0, 9;
|
|
a
|
|
2071
|
|
2061
|
|
2051
|
|
2041
|
|
2031
|
|
2021
|
|
2011
|
|
2001
|
|
1991
|
|
DROP TABLE t1;
|
|
#
|
|
# Bug #43029: FORCE INDEX FOR ORDER BY is ignored when join buffering
|
|
# is used
|
|
#
|
|
CREATE TABLE t1 (a INT, b INT, KEY (a));
|
|
INSERT INTO t1 VALUES (0, NULL), (1, NULL), (2, NULL), (3, NULL);
|
|
INSERT INTO t1 SELECT a+4, b FROM t1;
|
|
INSERT INTO t1 SELECT a+8, b FROM t1;
|
|
CREATE TABLE t2 (a INT, b INT);
|
|
INSERT INTO t2 VALUES (0,NULL), (1,NULL), (2,NULL), (3,NULL), (4,NULL);
|
|
INSERT INTO t2 SELECT a+4, b FROM t2;
|
|
# shouldn't have "using filesort"
|
|
EXPLAIN
|
|
SELECT * FROM t1 FORCE INDEX FOR ORDER BY (a), t2 WHERE t1.a < 2 ORDER BY t1.a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 range a a 5 NULL 2 Using where
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 10
|
|
# should have "using filesort"
|
|
EXPLAIN
|
|
SELECT * FROM t1 USE INDEX FOR ORDER BY (a), t2 WHERE t1.a < 2 ORDER BY t1.a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 range a a 5 NULL 2 Using where; Using temporary; Using filesort
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 10 Using join buffer
|
|
# should have "using filesort"
|
|
EXPLAIN
|
|
SELECT * FROM t1 FORCE INDEX FOR JOIN (a), t2 WHERE t1.a < 2 ORDER BY t1.a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 range a a 5 NULL 2 Using where; Using temporary; Using filesort
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 10 Using join buffer
|
|
DROP TABLE t1, t2;
|
|
#
|
|
# Bug #50394: Regression in EXPLAIN with index scan, LIMIT, GROUP BY and
|
|
# ORDER BY computed col
|
|
#
|
|
CREATE TABLE t1 ( a INT NOT NULL, b INT NOT NULL, KEY( a, b ) );
|
|
INSERT INTO t1 VALUES (1, 1), (2, 2), (3, 3), (4, 4), (5, 5);
|
|
INSERT INTO t1 SELECT a + 5, b + 5 FROM t1;
|
|
CREATE TABLE t2( a INT PRIMARY KEY, b INT );
|
|
INSERT INTO t2 VALUES (1, 1), (2, 2), (3, 3), (4, 4), (5, 5);
|
|
INSERT INTO t2 SELECT a + 5, b + 5 FROM t2;
|
|
EXPLAIN
|
|
SELECT count(*) AS c, t1.a
|
|
FROM t1 JOIN t2 ON t1.b = t2.a
|
|
WHERE t2.b = 1
|
|
GROUP BY t1.a
|
|
ORDER by c
|
|
LIMIT 2;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 index NULL a 8 NULL 10 Using index; Using temporary; Using filesort
|
|
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.b 1 Using where
|
|
DROP TABLE t1, t2;
|
|
End of 5.1 tests
|