mirror of
https://github.com/MariaDB/server.git
synced 2025-01-17 20:42:30 +01:00
4f9d984572
into gleb.loc:/home/uchum/work/bk/mysql-5.1-opt client/mysqldump.c: Auto merged mysql-test/r/join_outer.result: Auto merged mysql-test/r/kill.result: Auto merged mysql-test/r/view.result: Auto merged mysql-test/t/join_outer.test: Auto merged mysql-test/t/kill.test: Auto merged sql/field.h: Auto merged sql/item_func.cc: Auto merged sql/sp_head.cc: Auto merged sql/sql_base.cc: Auto merged mysql-test/r/mysqldump.result: Merge with 5.0-opt mysql-test/t/mysqldump.test: Merge with 5.0-opt mysql-test/t/view.test: Merge with 5.0-opt sql/sql_select.cc: Merge with 5.0-opt
1256 lines
40 KiB
Text
1256 lines
40 KiB
Text
drop table if exists t0,t1,t2,t3,t4,t5;
|
|
CREATE TABLE t1 (
|
|
grp int(11) default NULL,
|
|
a bigint(20) unsigned default NULL,
|
|
c char(10) NOT NULL default ''
|
|
) ENGINE=MyISAM;
|
|
INSERT INTO t1 VALUES (1,1,'a'),(2,2,'b'),(2,3,'c'),(3,4,'E'),(3,5,'C'),(3,6,'D'),(NULL,NULL,'');
|
|
create table t2 (id int, a bigint unsigned not null, c char(10), d int, primary key (a));
|
|
insert into t2 values (1,1,"a",1),(3,4,"A",4),(3,5,"B",5),(3,6,"C",6),(4,7,"D",7);
|
|
select t1.*,t2.* from t1 JOIN t2 where t1.a=t2.a;
|
|
grp a c id a c d
|
|
1 1 a 1 1 a 1
|
|
3 4 E 3 4 A 4
|
|
3 5 C 3 5 B 5
|
|
3 6 D 3 6 C 6
|
|
select t1.*,t2.* from t1 left join t2 on (t1.a=t2.a) order by t1.grp,t1.a,t2.c;
|
|
grp a c id a c d
|
|
NULL NULL NULL NULL NULL NULL
|
|
1 1 a 1 1 a 1
|
|
2 2 b NULL NULL NULL NULL
|
|
2 3 c NULL NULL NULL NULL
|
|
3 4 E 3 4 A 4
|
|
3 5 C 3 5 B 5
|
|
3 6 D 3 6 C 6
|
|
select t1.*,t2.* from { oj t2 left outer join t1 on (t1.a=t2.a) };
|
|
grp a c id a c d
|
|
1 1 a 1 1 a 1
|
|
3 4 E 3 4 A 4
|
|
3 5 C 3 5 B 5
|
|
3 6 D 3 6 C 6
|
|
NULL NULL NULL 4 7 D 7
|
|
select t1.*,t2.* from t1 as t0,{ oj t2 left outer join t1 on (t1.a=t2.a) } WHERE t0.a=2;
|
|
grp a c id a c d
|
|
1 1 a 1 1 a 1
|
|
3 4 E 3 4 A 4
|
|
3 5 C 3 5 B 5
|
|
3 6 D 3 6 C 6
|
|
NULL NULL NULL 4 7 D 7
|
|
select t1.*,t2.* from t1 left join t2 using (a);
|
|
grp a c id a c d
|
|
1 1 a 1 1 a 1
|
|
2 2 b NULL NULL NULL NULL
|
|
2 3 c NULL NULL NULL NULL
|
|
3 4 E 3 4 A 4
|
|
3 5 C 3 5 B 5
|
|
3 6 D 3 6 C 6
|
|
NULL NULL NULL NULL NULL NULL
|
|
select t1.*,t2.* from t1 left join t2 using (a) where t1.a=t2.a;
|
|
grp a c id a c d
|
|
1 1 a 1 1 a 1
|
|
3 4 E 3 4 A 4
|
|
3 5 C 3 5 B 5
|
|
3 6 D 3 6 C 6
|
|
select t1.*,t2.* from t1 left join t2 using (a,c);
|
|
grp a c id a c d
|
|
1 1 a 1 1 a 1
|
|
2 2 b NULL NULL NULL NULL
|
|
2 3 c NULL NULL NULL NULL
|
|
3 4 E NULL NULL NULL NULL
|
|
3 5 C NULL NULL NULL NULL
|
|
3 6 D NULL NULL NULL NULL
|
|
NULL NULL NULL NULL NULL NULL
|
|
select t1.*,t2.* from t1 left join t2 using (c);
|
|
grp a c id a c d
|
|
1 1 a 1 1 a 1
|
|
1 1 a 3 4 A 4
|
|
2 2 b 3 5 B 5
|
|
2 3 c 3 6 C 6
|
|
3 4 E NULL NULL NULL NULL
|
|
3 5 C 3 6 C 6
|
|
3 6 D 4 7 D 7
|
|
NULL NULL NULL NULL NULL NULL
|
|
select t1.*,t2.* from t1 natural left outer join t2;
|
|
grp a c id a c d
|
|
1 1 a 1 1 a 1
|
|
2 2 b NULL NULL NULL NULL
|
|
2 3 c NULL NULL NULL NULL
|
|
3 4 E NULL NULL NULL NULL
|
|
3 5 C NULL NULL NULL NULL
|
|
3 6 D NULL NULL NULL NULL
|
|
NULL NULL NULL NULL NULL NULL
|
|
select t1.*,t2.* from t1 left join t2 on (t1.a=t2.a) where t2.id=3;
|
|
grp a c id a c d
|
|
3 4 E 3 4 A 4
|
|
3 5 C 3 5 B 5
|
|
3 6 D 3 6 C 6
|
|
select t1.*,t2.* from t1 left join t2 on (t1.a=t2.a) where t2.id is null;
|
|
grp a c id a c d
|
|
2 2 b NULL NULL NULL NULL
|
|
2 3 c NULL NULL NULL NULL
|
|
NULL NULL NULL NULL NULL NULL
|
|
explain select t1.*,t2.* from t1,t2 where t1.a=t2.a and isnull(t2.a)=1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
|
|
explain select t1.*,t2.* from t1 left join t2 on t1.a=t2.a where isnull(t2.a)=1;
|
|
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 eq_ref PRIMARY PRIMARY 8 test.t1.a 1 Using where
|
|
select t1.*,t2.*,t3.a from t1 left join t2 on (t1.a=t2.a) left join t1 as t3 on (t2.a=t3.a);
|
|
grp a c id a c d a
|
|
1 1 a 1 1 a 1 1
|
|
2 2 b NULL NULL NULL NULL NULL
|
|
2 3 c NULL NULL NULL NULL NULL
|
|
3 4 E 3 4 A 4 4
|
|
3 5 C 3 5 B 5 5
|
|
3 6 D 3 6 C 6 6
|
|
NULL NULL NULL NULL NULL NULL NULL
|
|
explain select t1.*,t2.*,t3.a from t1 left join t2 on (t3.a=t2.a) left join t1 as t3 on (t1.a=t3.a);
|
|
ERROR 42S22: Unknown column 't3.a' in 'on clause'
|
|
select t1.*,t2.*,t3.a from t1 left join t2 on (t3.a=t2.a) left join t1 as t3 on (t1.a=t3.a);
|
|
ERROR 42S22: Unknown column 't3.a' in 'on clause'
|
|
select t1.*,t2.*,t3.a from t1 left join t2 on (t3.a=t2.a) left join t1 as t3 on (t2.a=t3.a);
|
|
ERROR 42S22: Unknown column 't3.a' in 'on clause'
|
|
select t1.*,t2.* from t1 inner join t2 using (a);
|
|
grp a c id a c d
|
|
1 1 a 1 1 a 1
|
|
3 4 E 3 4 A 4
|
|
3 5 C 3 5 B 5
|
|
3 6 D 3 6 C 6
|
|
select t1.*,t2.* from t1 inner join t2 on (t1.a=t2.a);
|
|
grp a c id a c d
|
|
1 1 a 1 1 a 1
|
|
3 4 E 3 4 A 4
|
|
3 5 C 3 5 B 5
|
|
3 6 D 3 6 C 6
|
|
select t1.*,t2.* from t1 natural join t2;
|
|
grp a c id a c d
|
|
1 1 a 1 1 a 1
|
|
drop table t1,t2;
|
|
CREATE TABLE t1 (
|
|
usr_id INT unsigned NOT NULL,
|
|
uniq_id INT unsigned NOT NULL AUTO_INCREMENT,
|
|
start_num INT unsigned NOT NULL DEFAULT 1,
|
|
increment INT unsigned NOT NULL DEFAULT 1,
|
|
PRIMARY KEY (uniq_id),
|
|
INDEX usr_uniq_idx (usr_id, uniq_id),
|
|
INDEX uniq_usr_idx (uniq_id, usr_id)
|
|
);
|
|
CREATE TABLE t2 (
|
|
id INT unsigned NOT NULL DEFAULT 0,
|
|
usr2_id INT unsigned NOT NULL DEFAULT 0,
|
|
max INT unsigned NOT NULL DEFAULT 0,
|
|
c_amount INT unsigned NOT NULL DEFAULT 0,
|
|
d_max INT unsigned NOT NULL DEFAULT 0,
|
|
d_num INT unsigned NOT NULL DEFAULT 0,
|
|
orig_time INT unsigned NOT NULL DEFAULT 0,
|
|
c_time INT unsigned NOT NULL DEFAULT 0,
|
|
active ENUM ("no","yes") NOT NULL,
|
|
PRIMARY KEY (id,usr2_id),
|
|
INDEX id_idx (id),
|
|
INDEX usr2_idx (usr2_id)
|
|
);
|
|
INSERT INTO t1 VALUES (3,NULL,0,50),(3,NULL,0,200),(3,NULL,0,25),(3,NULL,0,84676),(3,NULL,0,235),(3,NULL,0,10),(3,NULL,0,3098),(3,NULL,0,2947),(3,NULL,0,8987),(3,NULL,0,8347654),(3,NULL,0,20398),(3,NULL,0,8976),(3,NULL,0,500),(3,NULL,0,198);
|
|
SELECT t1.usr_id,t1.uniq_id,t1.increment,
|
|
t2.usr2_id,t2.c_amount,t2.max
|
|
FROM t1
|
|
LEFT JOIN t2 ON t2.id = t1.uniq_id
|
|
WHERE t1.uniq_id = 4
|
|
ORDER BY t2.c_amount;
|
|
usr_id uniq_id increment usr2_id c_amount max
|
|
3 4 84676 NULL NULL NULL
|
|
SELECT t1.usr_id,t1.uniq_id,t1.increment,
|
|
t2.usr2_id,t2.c_amount,t2.max
|
|
FROM t2
|
|
RIGHT JOIN t1 ON t2.id = t1.uniq_id
|
|
WHERE t1.uniq_id = 4
|
|
ORDER BY t2.c_amount;
|
|
usr_id uniq_id increment usr2_id c_amount max
|
|
3 4 84676 NULL NULL NULL
|
|
INSERT INTO t2 VALUES (2,3,3000,6000,0,0,746584,837484,'yes');
|
|
INSERT INTO t2 VALUES (2,3,3000,6000,0,0,746584,837484,'yes');
|
|
ERROR 23000: Duplicate entry '2-3' for key 'PRIMARY'
|
|
INSERT INTO t2 VALUES (7,3,1000,2000,0,0,746294,937484,'yes');
|
|
SELECT t1.usr_id,t1.uniq_id,t1.increment,t2.usr2_id,t2.c_amount,t2.max FROM t1 LEFT JOIN t2 ON t2.id = t1.uniq_id WHERE t1.uniq_id = 4 ORDER BY t2.c_amount;
|
|
usr_id uniq_id increment usr2_id c_amount max
|
|
3 4 84676 NULL NULL NULL
|
|
SELECT t1.usr_id,t1.uniq_id,t1.increment,t2.usr2_id,t2.c_amount,t2.max FROM t1 LEFT JOIN t2 ON t2.id = t1.uniq_id WHERE t1.uniq_id = 4 GROUP BY t2.c_amount;
|
|
usr_id uniq_id increment usr2_id c_amount max
|
|
3 4 84676 NULL NULL NULL
|
|
SELECT t1.usr_id,t1.uniq_id,t1.increment,t2.usr2_id,t2.c_amount,t2.max FROM t1 LEFT JOIN t2 ON t2.id = t1.uniq_id WHERE t1.uniq_id = 4;
|
|
usr_id uniq_id increment usr2_id c_amount max
|
|
3 4 84676 NULL NULL NULL
|
|
drop table t1,t2;
|
|
CREATE TABLE t1 (
|
|
cod_asig int(11) DEFAULT '0' NOT NULL,
|
|
desc_larga_cat varchar(80) DEFAULT '' NOT NULL,
|
|
desc_larga_cas varchar(80) DEFAULT '' NOT NULL,
|
|
desc_corta_cat varchar(40) DEFAULT '' NOT NULL,
|
|
desc_corta_cas varchar(40) DEFAULT '' NOT NULL,
|
|
cred_total double(3,1) DEFAULT '0.0' NOT NULL,
|
|
pre_requisit int(11),
|
|
co_requisit int(11),
|
|
preco_requisit int(11),
|
|
PRIMARY KEY (cod_asig)
|
|
);
|
|
INSERT INTO t1 VALUES (10360,'asdfggfg','Introduccion a los Ordenadores I','asdfggfg','Introduccio Ordinadors I',6.0,NULL,NULL,NULL);
|
|
INSERT INTO t1 VALUES (10361,'Components i Circuits Electronics I','Componentes y Circuitos Electronicos I','Components i Circuits Electronics I','Comp. i Circ. Electr. I',6.0,NULL,NULL,NULL);
|
|
INSERT INTO t1 VALUES (10362,'Laboratori d`Ordinadors','Laboratorio de Ordenadores','Laboratori d`Ordinadors','Laboratori Ordinadors',4.5,NULL,NULL,NULL);
|
|
INSERT INTO t1 VALUES (10363,'Tecniques de Comunicacio Oral i Escrita','Tecnicas de Comunicacion Oral y Escrita','Tecniques de Comunicacio Oral i Escrita','Tec. Com. Oral i Escrita',4.5,NULL,NULL,NULL);
|
|
INSERT INTO t1 VALUES (11403,'Projecte Fi de Carrera','Proyecto Fin de Carrera','Projecte Fi de Carrera','PFC',9.0,NULL,NULL,NULL);
|
|
INSERT INTO t1 VALUES (11404,'+lgebra lineal','Algebra lineal','+lgebra lineal','+lgebra lineal',15.0,NULL,NULL,NULL);
|
|
INSERT INTO t1 VALUES (11405,'+lgebra lineal','Algebra lineal','+lgebra lineal','+lgebra lineal',18.0,NULL,NULL,NULL);
|
|
INSERT INTO t1 VALUES (11406,'Calcul Infinitesimal','Cßlculo Infinitesimal','Calcul Infinitesimal','Calcul Infinitesimal',15.0,NULL,NULL,NULL);
|
|
CREATE TABLE t2 (
|
|
idAssignatura int(11) DEFAULT '0' NOT NULL,
|
|
Grup int(11) DEFAULT '0' NOT NULL,
|
|
Places smallint(6) DEFAULT '0' NOT NULL,
|
|
PlacesOcupades int(11) DEFAULT '0',
|
|
PRIMARY KEY (idAssignatura,Grup)
|
|
);
|
|
INSERT INTO t2 VALUES (10360,12,333,0);
|
|
INSERT INTO t2 VALUES (10361,30,2,0);
|
|
INSERT INTO t2 VALUES (10361,40,3,0);
|
|
INSERT INTO t2 VALUES (10360,45,10,0);
|
|
INSERT INTO t2 VALUES (10362,10,12,0);
|
|
INSERT INTO t2 VALUES (10360,55,2,0);
|
|
INSERT INTO t2 VALUES (10360,70,0,0);
|
|
INSERT INTO t2 VALUES (10360,565656,0,0);
|
|
INSERT INTO t2 VALUES (10360,32767,7,0);
|
|
INSERT INTO t2 VALUES (10360,33,8,0);
|
|
INSERT INTO t2 VALUES (10360,7887,85,0);
|
|
INSERT INTO t2 VALUES (11405,88,8,0);
|
|
INSERT INTO t2 VALUES (10360,0,55,0);
|
|
INSERT INTO t2 VALUES (10360,99,0,0);
|
|
INSERT INTO t2 VALUES (11411,30,10,0);
|
|
INSERT INTO t2 VALUES (11404,0,0,0);
|
|
INSERT INTO t2 VALUES (10362,11,111,0);
|
|
INSERT INTO t2 VALUES (10363,33,333,0);
|
|
INSERT INTO t2 VALUES (11412,55,0,0);
|
|
INSERT INTO t2 VALUES (50003,66,6,0);
|
|
INSERT INTO t2 VALUES (11403,5,0,0);
|
|
INSERT INTO t2 VALUES (11406,11,11,0);
|
|
INSERT INTO t2 VALUES (11410,11410,131,0);
|
|
INSERT INTO t2 VALUES (11416,11416,32767,0);
|
|
INSERT INTO t2 VALUES (11409,0,0,0);
|
|
CREATE TABLE t3 (
|
|
id int(11) NOT NULL auto_increment,
|
|
dni_pasaporte char(16) DEFAULT '' NOT NULL,
|
|
idPla int(11) DEFAULT '0' NOT NULL,
|
|
cod_asig int(11) DEFAULT '0' NOT NULL,
|
|
any smallint(6) DEFAULT '0' NOT NULL,
|
|
quatrimestre smallint(6) DEFAULT '0' NOT NULL,
|
|
estat char(1) DEFAULT 'M' NOT NULL,
|
|
PRIMARY KEY (id),
|
|
UNIQUE dni_pasaporte (dni_pasaporte,idPla),
|
|
UNIQUE dni_pasaporte_2 (dni_pasaporte,idPla,cod_asig,any,quatrimestre)
|
|
);
|
|
INSERT INTO t3 VALUES (1,'11111111',1,10362,98,1,'M');
|
|
CREATE TABLE t4 (
|
|
id int(11) NOT NULL auto_increment,
|
|
papa int(11) DEFAULT '0' NOT NULL,
|
|
fill int(11) DEFAULT '0' NOT NULL,
|
|
idPla int(11) DEFAULT '0' NOT NULL,
|
|
PRIMARY KEY (id),
|
|
KEY papa (idPla,papa),
|
|
UNIQUE papa_2 (idPla,papa,fill)
|
|
);
|
|
INSERT INTO t4 VALUES (1,-1,10360,1);
|
|
INSERT INTO t4 VALUES (2,-1,10361,1);
|
|
INSERT INTO t4 VALUES (3,-1,10362,1);
|
|
SELECT DISTINCT fill,desc_larga_cat,cred_total,Grup,Places,PlacesOcupades FROM t4 LEFT JOIN t3 ON t3.cod_asig=fill AND estat='S' AND dni_pasaporte='11111111' AND t3.idPla=1 , t2,t1 WHERE fill=t1.cod_asig AND Places>PlacesOcupades AND fill=idAssignatura AND t4.idPla=1 AND papa=-1;
|
|
fill desc_larga_cat cred_total Grup Places PlacesOcupades
|
|
10360 asdfggfg 6.0 0 55 0
|
|
10360 asdfggfg 6.0 12 333 0
|
|
10360 asdfggfg 6.0 33 8 0
|
|
10360 asdfggfg 6.0 45 10 0
|
|
10360 asdfggfg 6.0 55 2 0
|
|
10360 asdfggfg 6.0 7887 85 0
|
|
10360 asdfggfg 6.0 32767 7 0
|
|
10361 Components i Circuits Electronics I 6.0 30 2 0
|
|
10361 Components i Circuits Electronics I 6.0 40 3 0
|
|
10362 Laboratori d`Ordinadors 4.5 10 12 0
|
|
10362 Laboratori d`Ordinadors 4.5 11 111 0
|
|
SELECT DISTINCT fill,t3.idPla FROM t4 LEFT JOIN t3 ON t3.cod_asig=t4.fill AND t3.estat='S' AND t3.dni_pasaporte='1234' AND t3.idPla=1 ;
|
|
fill idPla
|
|
10360 NULL
|
|
10361 NULL
|
|
10362 NULL
|
|
INSERT INTO t3 VALUES (3,'1234',1,10360,98,1,'S');
|
|
SELECT DISTINCT fill,t3.idPla FROM t4 LEFT JOIN t3 ON t3.cod_asig=t4.fill AND t3.estat='S' AND t3.dni_pasaporte='1234' AND t3.idPla=1 ;
|
|
fill idPla
|
|
10360 1
|
|
10361 NULL
|
|
10362 NULL
|
|
drop table t1,t2,t3,test.t4;
|
|
CREATE TABLE t1 (
|
|
id smallint(5) unsigned NOT NULL auto_increment,
|
|
name char(60) DEFAULT '' NOT NULL,
|
|
PRIMARY KEY (id)
|
|
);
|
|
INSERT INTO t1 VALUES (1,'Antonio Paz');
|
|
INSERT INTO t1 VALUES (2,'Lilliana Angelovska');
|
|
INSERT INTO t1 VALUES (3,'Thimble Smith');
|
|
CREATE TABLE t2 (
|
|
id smallint(5) unsigned NOT NULL auto_increment,
|
|
owner smallint(5) unsigned DEFAULT '0' NOT NULL,
|
|
name char(60),
|
|
PRIMARY KEY (id)
|
|
);
|
|
INSERT INTO t2 VALUES (1,1,'El Gato');
|
|
INSERT INTO t2 VALUES (2,1,'Perrito');
|
|
INSERT INTO t2 VALUES (3,3,'Happy');
|
|
select t1.name, t2.name, t2.id from t1 left join t2 on (t1.id = t2.owner);
|
|
name name id
|
|
Antonio Paz El Gato 1
|
|
Antonio Paz Perrito 2
|
|
Lilliana Angelovska NULL NULL
|
|
Thimble Smith Happy 3
|
|
select t1.name, t2.name, t2.id from t1 left join t2 on (t1.id = t2.owner) where t2.id is null;
|
|
name name id
|
|
Lilliana Angelovska NULL NULL
|
|
explain select t1.name, t2.name, t2.id from t1 left join t2 on (t1.id = t2.owner) where t2.id is null;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 3 Using where; Not exists
|
|
explain select t1.name, t2.name, t2.id from t1 left join t2 on (t1.id = t2.owner) where t2.name is null;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 3 Using where
|
|
select count(*) from t1 left join t2 on (t1.id = t2.owner);
|
|
count(*)
|
|
4
|
|
select t1.name, t2.name, t2.id from t2 right join t1 on (t1.id = t2.owner);
|
|
name name id
|
|
Antonio Paz El Gato 1
|
|
Antonio Paz Perrito 2
|
|
Lilliana Angelovska NULL NULL
|
|
Thimble Smith Happy 3
|
|
select t1.name, t2.name, t2.id from t2 right join t1 on (t1.id = t2.owner) where t2.id is null;
|
|
name name id
|
|
Lilliana Angelovska NULL NULL
|
|
explain select t1.name, t2.name, t2.id from t2 right join t1 on (t1.id = t2.owner) where t2.id is null;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 3 Using where; Not exists
|
|
explain select t1.name, t2.name, t2.id from t2 right join t1 on (t1.id = t2.owner) where t2.name is null;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 3 Using where
|
|
select count(*) from t2 right join t1 on (t1.id = t2.owner);
|
|
count(*)
|
|
4
|
|
select t1.name, t2.name, t2.id,t3.id from t2 right join t1 on (t1.id = t2.owner) left join t1 as t3 on t3.id=t2.owner;
|
|
name name id id
|
|
Antonio Paz El Gato 1 1
|
|
Antonio Paz Perrito 2 1
|
|
Lilliana Angelovska NULL NULL NULL
|
|
Thimble Smith Happy 3 3
|
|
select t1.name, t2.name, t2.id,t3.id from t1 right join t2 on (t1.id = t2.owner) right join t1 as t3 on t3.id=t2.owner;
|
|
name name id id
|
|
Antonio Paz El Gato 1 1
|
|
Antonio Paz Perrito 2 1
|
|
NULL NULL NULL 2
|
|
Thimble Smith Happy 3 3
|
|
select t1.name, t2.name, t2.id, t2.owner, t3.id from t1 left join t2 on (t1.id = t2.owner) right join t1 as t3 on t3.id=t2.owner;
|
|
name name id owner id
|
|
Antonio Paz El Gato 1 1 1
|
|
Antonio Paz Perrito 2 1 1
|
|
NULL NULL NULL NULL 2
|
|
Thimble Smith Happy 3 3 3
|
|
drop table t1,t2;
|
|
create table t1 (id int not null, str char(10), index(str));
|
|
insert into t1 values (1, null), (2, null), (3, "foo"), (4, "bar");
|
|
select * from t1 where str is not null order by id;
|
|
id str
|
|
3 foo
|
|
4 bar
|
|
select * from t1 where str is null;
|
|
id str
|
|
1 NULL
|
|
2 NULL
|
|
drop table t1;
|
|
CREATE TABLE t1 (
|
|
t1_id bigint(21) NOT NULL auto_increment,
|
|
PRIMARY KEY (t1_id)
|
|
);
|
|
CREATE TABLE t2 (
|
|
t2_id bigint(21) NOT NULL auto_increment,
|
|
PRIMARY KEY (t2_id)
|
|
);
|
|
CREATE TABLE t3 (
|
|
t3_id bigint(21) NOT NULL auto_increment,
|
|
PRIMARY KEY (t3_id)
|
|
);
|
|
CREATE TABLE t4 (
|
|
seq_0_id bigint(21) DEFAULT '0' NOT NULL,
|
|
seq_1_id bigint(21) DEFAULT '0' NOT NULL,
|
|
KEY seq_0_id (seq_0_id),
|
|
KEY seq_1_id (seq_1_id)
|
|
);
|
|
CREATE TABLE t5 (
|
|
seq_0_id bigint(21) DEFAULT '0' NOT NULL,
|
|
seq_1_id bigint(21) DEFAULT '0' NOT NULL,
|
|
KEY seq_1_id (seq_1_id),
|
|
KEY seq_0_id (seq_0_id)
|
|
);
|
|
insert into t1 values (1);
|
|
insert into t2 values (1);
|
|
insert into t3 values (1);
|
|
insert into t4 values (1,1);
|
|
insert into t5 values (1,1);
|
|
explain select * from t3 left join t4 on t4.seq_1_id = t2.t2_id left join t1 on t1.t1_id = t4.seq_0_id left join t5 on t5.seq_0_id = t1.t1_id left join t2 on t2.t2_id = t5.seq_1_id where t3.t3_id = 23;
|
|
ERROR 42S22: Unknown column 't2.t2_id' in 'on clause'
|
|
drop table t1,t2,t3,t4,t5;
|
|
create table t1 (n int, m int, o int, key(n));
|
|
create table t2 (n int not null, m int, o int, primary key(n));
|
|
insert into t1 values (1, 2, 11), (1, 2, 7), (2, 2, 8), (1,2,9),(1,3,9);
|
|
insert into t2 values (1, 2, 3),(2, 2, 8), (4,3,9),(3,2,10);
|
|
select t1.*, t2.* from t1 left join t2 on t1.n = t2.n and
|
|
t1.m = t2.m where t1.n = 1;
|
|
n m o n m o
|
|
1 2 11 1 2 3
|
|
1 2 7 1 2 3
|
|
1 2 9 1 2 3
|
|
1 3 9 NULL NULL NULL
|
|
select t1.*, t2.* from t1 left join t2 on t1.n = t2.n and
|
|
t1.m = t2.m where t1.n = 1 order by t1.o;
|
|
n m o n m o
|
|
1 2 7 1 2 3
|
|
1 2 9 1 2 3
|
|
1 3 9 NULL NULL NULL
|
|
1 2 11 1 2 3
|
|
drop table t1,t2;
|
|
CREATE TABLE t1 (id1 INT NOT NULL PRIMARY KEY, dat1 CHAR(1), id2 INT);
|
|
INSERT INTO t1 VALUES (1,'a',1);
|
|
INSERT INTO t1 VALUES (2,'b',1);
|
|
INSERT INTO t1 VALUES (3,'c',2);
|
|
CREATE TABLE t2 (id2 INT NOT NULL PRIMARY KEY, dat2 CHAR(1));
|
|
INSERT INTO t2 VALUES (1,'x');
|
|
INSERT INTO t2 VALUES (2,'y');
|
|
INSERT INTO t2 VALUES (3,'z');
|
|
SELECT t2.id2 FROM t2 LEFT OUTER JOIN t1 ON t1.id2 = t2.id2 WHERE id1 IS NULL;
|
|
id2
|
|
3
|
|
SELECT t2.id2 FROM t2 NATURAL LEFT OUTER JOIN t1 WHERE id1 IS NULL;
|
|
id2
|
|
3
|
|
drop table t1,t2;
|
|
create table t1 ( color varchar(20), name varchar(20) );
|
|
insert into t1 values ( 'red', 'apple' );
|
|
insert into t1 values ( 'yellow', 'banana' );
|
|
insert into t1 values ( 'green', 'lime' );
|
|
insert into t1 values ( 'black', 'grape' );
|
|
insert into t1 values ( 'blue', 'blueberry' );
|
|
create table t2 ( count int, color varchar(20) );
|
|
insert into t2 values (10, 'green');
|
|
insert into t2 values (5, 'black');
|
|
insert into t2 values (15, 'white');
|
|
insert into t2 values (7, 'green');
|
|
select * from t1;
|
|
color name
|
|
red apple
|
|
yellow banana
|
|
green lime
|
|
black grape
|
|
blue blueberry
|
|
select * from t2;
|
|
count color
|
|
10 green
|
|
5 black
|
|
15 white
|
|
7 green
|
|
select * from t2 natural join t1;
|
|
color count name
|
|
green 10 lime
|
|
green 7 lime
|
|
black 5 grape
|
|
select t2.count, t1.name from t2 natural join t1;
|
|
count name
|
|
10 lime
|
|
7 lime
|
|
5 grape
|
|
select t2.count, t1.name from t2 inner join t1 using (color);
|
|
count name
|
|
10 lime
|
|
7 lime
|
|
5 grape
|
|
drop table t1;
|
|
drop table t2;
|
|
CREATE TABLE t1 (
|
|
pcode varchar(8) DEFAULT '' NOT NULL
|
|
);
|
|
INSERT INTO t1 VALUES ('kvw2000'),('kvw2001'),('kvw3000'),('kvw3001'),('kvw3002'),('kvw3500'),('kvw3501'),('kvw3502'),('kvw3800'),('kvw3801'),('kvw3802'),('kvw3900'),('kvw3901'),('kvw3902'),('kvw4000'),('kvw4001'),('kvw4002'),('kvw4200'),('kvw4500'),('kvw5000'),('kvw5001'),('kvw5500'),('kvw5510'),('kvw5600'),('kvw5601'),('kvw6000'),('klw1000'),('klw1020'),('klw1500'),('klw2000'),('klw2001'),('klw2002'),('kld2000'),('klw2500'),('kmw1000'),('kmw1500'),('kmw2000'),('kmw2001'),('kmw2100'),('kmw3000'),('kmw3200');
|
|
CREATE TABLE t2 (
|
|
pcode varchar(8) DEFAULT '' NOT NULL,
|
|
KEY pcode (pcode)
|
|
);
|
|
INSERT INTO t2 VALUES ('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw2000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3000'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw3500'),('kvw6000'),('kvw6000'),('kld2000');
|
|
SELECT t1.pcode, IF(ISNULL(t2.pcode), 0, COUNT(*)) AS count FROM t1
|
|
LEFT JOIN t2 ON t1.pcode = t2.pcode GROUP BY t1.pcode;
|
|
pcode count
|
|
kld2000 1
|
|
klw1000 0
|
|
klw1020 0
|
|
klw1500 0
|
|
klw2000 0
|
|
klw2001 0
|
|
klw2002 0
|
|
klw2500 0
|
|
kmw1000 0
|
|
kmw1500 0
|
|
kmw2000 0
|
|
kmw2001 0
|
|
kmw2100 0
|
|
kmw3000 0
|
|
kmw3200 0
|
|
kvw2000 26
|
|
kvw2001 0
|
|
kvw3000 36
|
|
kvw3001 0
|
|
kvw3002 0
|
|
kvw3500 26
|
|
kvw3501 0
|
|
kvw3502 0
|
|
kvw3800 0
|
|
kvw3801 0
|
|
kvw3802 0
|
|
kvw3900 0
|
|
kvw3901 0
|
|
kvw3902 0
|
|
kvw4000 0
|
|
kvw4001 0
|
|
kvw4002 0
|
|
kvw4200 0
|
|
kvw4500 0
|
|
kvw5000 0
|
|
kvw5001 0
|
|
kvw5500 0
|
|
kvw5510 0
|
|
kvw5600 0
|
|
kvw5601 0
|
|
kvw6000 2
|
|
SELECT SQL_BIG_RESULT t1.pcode, IF(ISNULL(t2.pcode), 0, COUNT(*)) AS count FROM t1 LEFT JOIN t2 ON t1.pcode = t2.pcode GROUP BY t1.pcode;
|
|
pcode count
|
|
kld2000 1
|
|
klw1000 0
|
|
klw1020 0
|
|
klw1500 0
|
|
klw2000 0
|
|
klw2001 0
|
|
klw2002 0
|
|
klw2500 0
|
|
kmw1000 0
|
|
kmw1500 0
|
|
kmw2000 0
|
|
kmw2001 0
|
|
kmw2100 0
|
|
kmw3000 0
|
|
kmw3200 0
|
|
kvw2000 26
|
|
kvw2001 0
|
|
kvw3000 36
|
|
kvw3001 0
|
|
kvw3002 0
|
|
kvw3500 26
|
|
kvw3501 0
|
|
kvw3502 0
|
|
kvw3800 0
|
|
kvw3801 0
|
|
kvw3802 0
|
|
kvw3900 0
|
|
kvw3901 0
|
|
kvw3902 0
|
|
kvw4000 0
|
|
kvw4001 0
|
|
kvw4002 0
|
|
kvw4200 0
|
|
kvw4500 0
|
|
kvw5000 0
|
|
kvw5001 0
|
|
kvw5500 0
|
|
kvw5510 0
|
|
kvw5600 0
|
|
kvw5601 0
|
|
kvw6000 2
|
|
drop table t1,t2;
|
|
CREATE TABLE t1 (
|
|
id int(11),
|
|
pid int(11),
|
|
rep_del tinyint(4),
|
|
KEY id (id),
|
|
KEY pid (pid)
|
|
);
|
|
INSERT INTO t1 VALUES (1,NULL,NULL);
|
|
INSERT INTO t1 VALUES (2,1,NULL);
|
|
select * from t1 LEFT JOIN t1 t2 ON (t1.id=t2.pid) AND t2.rep_del IS NULL;
|
|
id pid rep_del id pid rep_del
|
|
1 NULL NULL 2 1 NULL
|
|
2 1 NULL NULL NULL NULL
|
|
create index rep_del ON t1(rep_del);
|
|
select * from t1 LEFT JOIN t1 t2 ON (t1.id=t2.pid) AND t2.rep_del IS NULL;
|
|
id pid rep_del id pid rep_del
|
|
1 NULL NULL 2 1 NULL
|
|
2 1 NULL NULL NULL NULL
|
|
drop table t1;
|
|
CREATE TABLE t1 (
|
|
id int(11) DEFAULT '0' NOT NULL,
|
|
name tinytext DEFAULT '' NOT NULL,
|
|
UNIQUE id (id)
|
|
);
|
|
Warnings:
|
|
Warning 1101 BLOB/TEXT column 'name' can't have a default value
|
|
INSERT INTO t1 VALUES (1,'yes'),(2,'no');
|
|
CREATE TABLE t2 (
|
|
id int(11) DEFAULT '0' NOT NULL,
|
|
idx int(11) DEFAULT '0' NOT NULL,
|
|
UNIQUE id (id,idx)
|
|
);
|
|
INSERT INTO t2 VALUES (1,1);
|
|
explain SELECT * from t1 left join t2 on t1.id=t2.id where t2.id IS NULL;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 2
|
|
1 SIMPLE t2 ref id id 4 test.t1.id 1 Using where; Using index; Not exists
|
|
SELECT * from t1 left join t2 on t1.id=t2.id where t2.id IS NULL;
|
|
id name id idx
|
|
2 no NULL NULL
|
|
drop table t1,t2;
|
|
create table t1 (bug_id mediumint, reporter mediumint);
|
|
create table t2 (bug_id mediumint, who mediumint, index(who));
|
|
insert into t2 values (1,1),(1,2);
|
|
insert into t1 values (1,1),(2,1);
|
|
SELECT * FROM t1 LEFT JOIN t2 ON (t1.bug_id = t2.bug_id AND t2.who = 2) WHERE (t1.reporter = 2 OR t2.who = 2);
|
|
bug_id reporter bug_id who
|
|
1 1 1 2
|
|
drop table t1,t2;
|
|
create table t1 (fooID smallint unsigned auto_increment, primary key (fooID));
|
|
create table t2 (fooID smallint unsigned not null, barID smallint unsigned not null, primary key (fooID,barID));
|
|
insert into t1 (fooID) values (10),(20),(30);
|
|
insert into t2 values (10,1),(20,2),(30,3);
|
|
explain select * from t2 left join t1 on t1.fooID = t2.fooID and t1.fooID = 30;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 index NULL PRIMARY 4 NULL 3 Using index
|
|
1 SIMPLE t1 const PRIMARY PRIMARY 2 const 1 Using index
|
|
select * from t2 left join t1 on t1.fooID = t2.fooID and t1.fooID = 30;
|
|
fooID barID fooID
|
|
10 1 NULL
|
|
20 2 NULL
|
|
30 3 30
|
|
select * from t2 left join t1 ignore index(primary) on t1.fooID = t2.fooID and t1.fooID = 30;
|
|
fooID barID fooID
|
|
10 1 NULL
|
|
20 2 NULL
|
|
30 3 30
|
|
drop table t1,t2;
|
|
create table t1 (i int);
|
|
create table t2 (i int);
|
|
create table t3 (i int);
|
|
insert into t1 values(1),(2);
|
|
insert into t2 values(2),(3);
|
|
insert into t3 values(2),(4);
|
|
select * from t1 natural left join t2 natural left join t3;
|
|
i
|
|
1
|
|
2
|
|
select * from t1 natural left join t2 where (t2.i is not null)=0;
|
|
i
|
|
1
|
|
select * from t1 natural left join t2 where (t2.i is not null) is not null;
|
|
i
|
|
1
|
|
2
|
|
select * from t1 natural left join t2 where (i is not null)=0;
|
|
i
|
|
select * from t1 natural left join t2 where (i is not null) is not null;
|
|
i
|
|
1
|
|
2
|
|
drop table t1,t2,t3;
|
|
create table t1 (f1 integer,f2 integer,f3 integer);
|
|
create table t2 (f2 integer,f4 integer);
|
|
create table t3 (f3 integer,f5 integer);
|
|
select * from t1
|
|
left outer join t2 using (f2)
|
|
left outer join t3 using (f3);
|
|
f3 f2 f1 f4 f5
|
|
drop table t1,t2,t3;
|
|
create table t1 (a1 int, a2 int);
|
|
create table t2 (b1 int not null, b2 int);
|
|
create table t3 (c1 int, c2 int);
|
|
insert into t1 values (1,2), (2,2), (3,2);
|
|
insert into t2 values (1,3), (2,3);
|
|
insert into t3 values (2,4), (3,4);
|
|
select * from t1 left join t2 on b1 = a1 left join t3 on c1 = a1 and b1 is null;
|
|
a1 a2 b1 b2 c1 c2
|
|
1 2 1 3 NULL NULL
|
|
2 2 2 3 NULL NULL
|
|
3 2 NULL NULL 3 4
|
|
explain select * from t1 left join t2 on b1 = a1 left join t3 on c1 = a1 and b1 is null;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 3
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 2
|
|
1 SIMPLE t3 ALL NULL NULL NULL NULL 2
|
|
drop table t1, t2, t3;
|
|
create table t1 (
|
|
a int(11),
|
|
b char(10),
|
|
key (a)
|
|
);
|
|
insert into t1 (a) values (1),(2),(3),(4);
|
|
create table t2 (a int);
|
|
select * from t1 left join t2 on t1.a=t2.a where not (t2.a <=> t1.a);
|
|
a b a
|
|
1 NULL NULL
|
|
2 NULL NULL
|
|
3 NULL NULL
|
|
4 NULL NULL
|
|
select * from t1 left join t2 on t1.a=t2.a having not (t2.a <=> t1.a);
|
|
a b a
|
|
1 NULL NULL
|
|
2 NULL NULL
|
|
3 NULL NULL
|
|
4 NULL NULL
|
|
drop table t1,t2;
|
|
create table t1 (
|
|
match_id tinyint(3) unsigned not null auto_increment,
|
|
home tinyint(3) unsigned default '0',
|
|
unique key match_id (match_id),
|
|
key match_id_2 (match_id)
|
|
);
|
|
insert into t1 values("1", "2");
|
|
create table t2 (
|
|
player_id tinyint(3) unsigned default '0',
|
|
match_1_h tinyint(3) unsigned default '0',
|
|
key player_id (player_id)
|
|
);
|
|
insert into t2 values("1", "5");
|
|
insert into t2 values("2", "9");
|
|
insert into t2 values("3", "3");
|
|
insert into t2 values("4", "7");
|
|
insert into t2 values("5", "6");
|
|
insert into t2 values("6", "8");
|
|
insert into t2 values("7", "4");
|
|
insert into t2 values("8", "12");
|
|
insert into t2 values("9", "11");
|
|
insert into t2 values("10", "10");
|
|
explain select s.*, '*', m.*, (s.match_1_h - m.home) UUX from
|
|
(t2 s left join t1 m on m.match_id = 1)
|
|
order by m.match_id desc;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE s ALL NULL NULL NULL NULL 10 Using temporary; Using filesort
|
|
1 SIMPLE m const match_id,match_id_2 match_id 1 const 1
|
|
explain select s.*, '*', m.*, (s.match_1_h - m.home) UUX from
|
|
(t2 s left join t1 m on m.match_id = 1)
|
|
order by UUX desc;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE s ALL NULL NULL NULL NULL 10 Using temporary; Using filesort
|
|
1 SIMPLE m const match_id,match_id_2 match_id 1 const 1
|
|
select s.*, '*', m.*, (s.match_1_h - m.home) UUX from
|
|
(t2 s left join t1 m on m.match_id = 1)
|
|
order by UUX desc;
|
|
player_id match_1_h * match_id home UUX
|
|
8 12 * 1 2 10
|
|
9 11 * 1 2 9
|
|
10 10 * 1 2 8
|
|
2 9 * 1 2 7
|
|
6 8 * 1 2 6
|
|
4 7 * 1 2 5
|
|
5 6 * 1 2 4
|
|
1 5 * 1 2 3
|
|
7 4 * 1 2 2
|
|
3 3 * 1 2 1
|
|
explain select s.*, '*', m.*, (s.match_1_h - m.home) UUX from
|
|
t2 s straight_join t1 m where m.match_id = 1
|
|
order by UUX desc;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE s ALL NULL NULL NULL NULL 10 Using temporary; Using filesort
|
|
1 SIMPLE m const match_id,match_id_2 match_id 1 const 1
|
|
select s.*, '*', m.*, (s.match_1_h - m.home) UUX from
|
|
t2 s straight_join t1 m where m.match_id = 1
|
|
order by UUX desc;
|
|
player_id match_1_h * match_id home UUX
|
|
8 12 * 1 2 10
|
|
9 11 * 1 2 9
|
|
10 10 * 1 2 8
|
|
2 9 * 1 2 7
|
|
6 8 * 1 2 6
|
|
4 7 * 1 2 5
|
|
5 6 * 1 2 4
|
|
1 5 * 1 2 3
|
|
7 4 * 1 2 2
|
|
3 3 * 1 2 1
|
|
drop table t1, t2;
|
|
create table t1 (a int, b int, unique index idx (a, b));
|
|
create table t2 (a int, b int, c int, unique index idx (a, b));
|
|
insert into t1 values (1, 10), (1,11), (2,10), (2,11);
|
|
insert into t2 values (1,10,3);
|
|
select t1.a, t1.b, t2.c from t1 left join t2
|
|
on t1.a=t2.a and t1.b=t2.b and t2.c=3
|
|
where t1.a=1 and t2.c is null;
|
|
a b c
|
|
1 11 NULL
|
|
drop table t1, t2;
|
|
CREATE TABLE t1 (
|
|
ts_id bigint(20) default NULL,
|
|
inst_id tinyint(4) default NULL,
|
|
flag_name varchar(64) default NULL,
|
|
flag_value text,
|
|
UNIQUE KEY ts_id (ts_id,inst_id,flag_name)
|
|
) ENGINE=MyISAM DEFAULT CHARSET=utf8;
|
|
CREATE TABLE t2 (
|
|
ts_id bigint(20) default NULL,
|
|
inst_id tinyint(4) default NULL,
|
|
flag_name varchar(64) default NULL,
|
|
flag_value text,
|
|
UNIQUE KEY ts_id (ts_id,inst_id,flag_name)
|
|
) ENGINE=MyISAM DEFAULT CHARSET=utf8;
|
|
INSERT INTO t1 VALUES
|
|
(111056548820001, 0, 'flag1', NULL),
|
|
(111056548820001, 0, 'flag2', NULL),
|
|
(2, 0, 'other_flag', NULL);
|
|
INSERT INTO t2 VALUES
|
|
(111056548820001, 3, 'flag1', 'sss');
|
|
SELECT t1.flag_name,t2.flag_value
|
|
FROM t1 LEFT JOIN t2
|
|
ON (t1.ts_id = t2.ts_id AND t1.flag_name = t2.flag_name AND
|
|
t2.inst_id = 3)
|
|
WHERE t1.inst_id = 0 AND t1.ts_id=111056548820001 AND
|
|
t2.flag_value IS NULL;
|
|
flag_name flag_value
|
|
flag2 NULL
|
|
DROP TABLE t1,t2;
|
|
CREATE TABLE t1 (
|
|
id int(11) unsigned NOT NULL auto_increment,
|
|
text_id int(10) unsigned default NULL,
|
|
PRIMARY KEY (id)
|
|
);
|
|
INSERT INTO t1 VALUES("1", "0");
|
|
INSERT INTO t1 VALUES("2", "10");
|
|
CREATE TABLE t2 (
|
|
text_id char(3) NOT NULL default '',
|
|
language_id char(3) NOT NULL default '',
|
|
text_data text,
|
|
PRIMARY KEY (text_id,language_id)
|
|
);
|
|
INSERT INTO t2 VALUES("0", "EN", "0-EN");
|
|
INSERT INTO t2 VALUES("0", "SV", "0-SV");
|
|
INSERT INTO t2 VALUES("10", "EN", "10-EN");
|
|
INSERT INTO t2 VALUES("10", "SV", "10-SV");
|
|
SELECT t1.id, t1.text_id, t2.text_data
|
|
FROM t1 LEFT JOIN t2
|
|
ON t1.text_id = t2.text_id
|
|
AND t2.language_id = 'SV'
|
|
WHERE (t1.id LIKE '%' OR t2.text_data LIKE '%');
|
|
id text_id text_data
|
|
1 0 0-SV
|
|
2 10 10-SV
|
|
DROP TABLE t1, t2;
|
|
CREATE TABLE t0 (a0 int PRIMARY KEY);
|
|
CREATE TABLE t1 (a1 int PRIMARY KEY);
|
|
CREATE TABLE t2 (a2 int);
|
|
CREATE TABLE t3 (a3 int);
|
|
INSERT INTO t0 VALUES (1);
|
|
INSERT INTO t1 VALUES (1);
|
|
INSERT INTO t2 VALUES (1), (2);
|
|
INSERT INTO t3 VALUES (1), (2);
|
|
SELECT * FROM t1 LEFT JOIN t2 ON a1=0;
|
|
a1 a2
|
|
1 NULL
|
|
EXPLAIN SELECT * FROM t1 LEFT JOIN t2 ON a1=0;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 system NULL NULL NULL NULL 1
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 2
|
|
SELECT * FROM t1 LEFT JOIN (t2,t3) ON a1=0;
|
|
a1 a2 a3
|
|
1 NULL NULL
|
|
EXPLAIN SELECT * FROM t1 LEFT JOIN (t2,t3) ON a1=0;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 system NULL NULL NULL NULL 1
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 2
|
|
1 SIMPLE t3 ALL NULL NULL NULL NULL 2
|
|
SELECT * FROM t0, t1 LEFT JOIN (t2,t3) ON a1=0 WHERE a0=a1;
|
|
a0 a1 a2 a3
|
|
1 1 NULL NULL
|
|
EXPLAIN SELECT * FROM t0, t1 LEFT JOIN (t2,t3) ON a1=0 WHERE a0=a1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t0 system PRIMARY NULL NULL NULL 1
|
|
1 SIMPLE t1 system PRIMARY NULL NULL NULL 1
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 2
|
|
1 SIMPLE t3 ALL NULL NULL NULL NULL 2
|
|
INSERT INTO t0 VALUES (0);
|
|
INSERT INTO t1 VALUES (0);
|
|
SELECT * FROM t0, t1 LEFT JOIN (t2,t3) ON a1=5 WHERE a0=a1 AND a0=1;
|
|
a0 a1 a2 a3
|
|
1 1 NULL NULL
|
|
EXPLAIN SELECT * FROM t0, t1 LEFT JOIN (t2,t3) ON a1=5 WHERE a0=a1 AND a0=1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t0 const PRIMARY PRIMARY 4 const 1 Using index
|
|
1 SIMPLE t1 const PRIMARY PRIMARY 4 const 1 Using index
|
|
1 SIMPLE t2 ALL NULL NULL NULL NULL 2
|
|
1 SIMPLE t3 ALL NULL NULL NULL NULL 2
|
|
drop table t1,t2;
|
|
create table t1 (a int, b int);
|
|
insert into t1 values (1,1),(2,2),(3,3);
|
|
create table t2 (a int, b int);
|
|
insert into t2 values (1,1), (2,2);
|
|
select * from t2 right join t1 on t2.a=t1.a;
|
|
a b a b
|
|
1 1 1 1
|
|
2 2 2 2
|
|
NULL NULL 3 3
|
|
select straight_join * from t2 right join t1 on t2.a=t1.a;
|
|
a b a b
|
|
1 1 1 1
|
|
2 2 2 2
|
|
NULL NULL 3 3
|
|
DROP TABLE t0,t1,t2,t3;
|
|
CREATE TABLE t1 (a int PRIMARY KEY, b int);
|
|
CREATE TABLE t2 (a int PRIMARY KEY, b int);
|
|
INSERT INTO t1 VALUES (1,1), (2,1), (3,1), (4,2);
|
|
INSERT INTO t2 VALUES (1,2), (2,2);
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.a;
|
|
a b a b
|
|
1 1 1 2
|
|
2 1 2 2
|
|
3 1 NULL NULL
|
|
4 2 NULL NULL
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.a WHERE t1.b=1;
|
|
a b a b
|
|
1 1 1 2
|
|
2 1 2 2
|
|
3 1 NULL NULL
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.a
|
|
WHERE t1.b=1 XOR (NOT ISNULL(t2.a) AND t2.b=1);
|
|
a b a b
|
|
1 1 1 2
|
|
2 1 2 2
|
|
3 1 NULL NULL
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.a WHERE not(0+(t1.a=30 and t2.b=1));
|
|
a b a b
|
|
1 1 1 2
|
|
2 1 2 2
|
|
3 1 NULL NULL
|
|
4 2 NULL NULL
|
|
DROP TABLE t1,t2;
|
|
set group_concat_max_len=5;
|
|
create table t1 (a int, b varchar(20));
|
|
create table t2 (a int, c varchar(20));
|
|
insert into t1 values (1,"aaaaaaaaaa"),(2,"bbbbbbbbbb");
|
|
insert into t2 values (1,"cccccccccc"),(2,"dddddddddd");
|
|
select group_concat(t1.b,t2.c) from t1 left join t2 using(a) group by t1.a;
|
|
group_concat(t1.b,t2.c)
|
|
aaaaa
|
|
bbbbb
|
|
Warnings:
|
|
Warning 1260 2 line(s) were cut by GROUP_CONCAT()
|
|
select group_concat(t1.b,t2.c) from t1 inner join t2 using(a) group by t1.a;
|
|
group_concat(t1.b,t2.c)
|
|
aaaaa
|
|
bbbbb
|
|
Warnings:
|
|
Warning 1260 2 line(s) were cut by GROUP_CONCAT()
|
|
select group_concat(t1.b,t2.c) from t1 left join t2 using(a) group by a;
|
|
group_concat(t1.b,t2.c)
|
|
aaaaa
|
|
bbbbb
|
|
Warnings:
|
|
Warning 1260 2 line(s) were cut by GROUP_CONCAT()
|
|
select group_concat(t1.b,t2.c) from t1 inner join t2 using(a) group by a;
|
|
group_concat(t1.b,t2.c)
|
|
aaaaa
|
|
bbbbb
|
|
Warnings:
|
|
Warning 1260 2 line(s) were cut by GROUP_CONCAT()
|
|
drop table t1, t2;
|
|
set group_concat_max_len=default;
|
|
create table t1 (gid smallint(5) unsigned not null, x int(11) not null, y int(11) not null, art int(11) not null, primary key (gid,x,y));
|
|
insert t1 values (1, -5, -8, 2), (1, 2, 2, 1), (1, 1, 1, 1);
|
|
create table t2 (gid smallint(5) unsigned not null, x int(11) not null, y int(11) not null, id int(11) not null, primary key (gid,id,x,y), key id (id));
|
|
insert t2 values (1, -5, -8, 1), (1, 1, 1, 1), (1, 2, 2, 1);
|
|
create table t3 ( set_id smallint(5) unsigned not null, id tinyint(4) unsigned not null, name char(12) not null, primary key (id,set_id));
|
|
insert t3 values (0, 1, 'a'), (1, 1, 'b'), (0, 2, 'c'), (1, 2, 'd'), (1, 3, 'e'), (1, 4, 'f'), (1, 5, 'g'), (1, 6, 'h');
|
|
explain select name from t1 left join t2 on t1.x = t2.x and t1.y = t2.y
|
|
left join t3 on t1.art = t3.id where t2.id =1 and t2.x = -5 and t2.y =-8
|
|
and t1.gid =1 and t2.gid =1 and t3.set_id =1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 const PRIMARY PRIMARY 10 const,const,const 1
|
|
1 SIMPLE t2 const PRIMARY,id PRIMARY 14 const,const,const,const 1 Using index
|
|
1 SIMPLE t3 const PRIMARY PRIMARY 3 const,const 1
|
|
drop tables t1,t2,t3;
|
|
CREATE TABLE t1 (EMPNUM INT, GRP INT);
|
|
INSERT INTO t1 VALUES (0, 10);
|
|
INSERT INTO t1 VALUES (2, 30);
|
|
CREATE TABLE t2 (EMPNUM INT, NAME CHAR(5));
|
|
INSERT INTO t2 VALUES (0, 'KERI');
|
|
INSERT INTO t2 VALUES (9, 'BARRY');
|
|
CREATE VIEW v1 AS
|
|
SELECT COALESCE(t2.EMPNUM,t1.EMPNUM) AS EMPNUM, NAME, GRP
|
|
FROM t2 LEFT OUTER JOIN t1 ON t2.EMPNUM=t1.EMPNUM;
|
|
SELECT * FROM v1;
|
|
EMPNUM NAME GRP
|
|
0 KERI 10
|
|
9 BARRY NULL
|
|
SELECT * FROM v1 WHERE EMPNUM < 10;
|
|
EMPNUM NAME GRP
|
|
0 KERI 10
|
|
9 BARRY NULL
|
|
DROP VIEW v1;
|
|
DROP TABLE t1,t2;
|
|
CREATE TABLE t1 (c11 int);
|
|
CREATE TABLE t2 (c21 int);
|
|
INSERT INTO t1 VALUES (30), (40), (50);
|
|
INSERT INTO t2 VALUES (300), (400), (500);
|
|
SELECT * FROM t1 LEFT JOIN t2 ON (c11=c21 AND c21=30) WHERE c11=40;
|
|
c11 c21
|
|
40 NULL
|
|
DROP TABLE t1, t2;
|
|
CREATE TABLE t1 (a int PRIMARY KEY, b int);
|
|
CREATE TABLE t2 (a int PRIMARY KEY, b int);
|
|
INSERT INTO t1 VALUES (1,2), (2,1), (3,2), (4,3), (5,6), (6,5), (7,8), (8,7), (9,10);
|
|
INSERT INTO t2 VALUES (3,0), (4,1), (6,4), (7,5);
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE t2.b <= t1.a AND t1.a <= t1.b;
|
|
a b a b
|
|
7 8 7 5
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE t1.a BETWEEN t2.b AND t1.b;
|
|
a b a b
|
|
7 8 7 5
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE NOT(t1.a NOT BETWEEN t2.b AND t1.b);
|
|
a b a b
|
|
7 8 7 5
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE t2.b > t1.a OR t1.a > t1.b;
|
|
a b a b
|
|
2 1 NULL NULL
|
|
3 2 3 0
|
|
4 3 4 1
|
|
6 5 6 4
|
|
8 7 NULL NULL
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE t1.a NOT BETWEEN t2.b AND t1.b;
|
|
a b a b
|
|
2 1 NULL NULL
|
|
3 2 3 0
|
|
4 3 4 1
|
|
6 5 6 4
|
|
8 7 NULL NULL
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE NOT(t1.a BETWEEN t2.b AND t1.b);
|
|
a b a b
|
|
2 1 NULL NULL
|
|
3 2 3 0
|
|
4 3 4 1
|
|
6 5 6 4
|
|
8 7 NULL NULL
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE t1.a = t2.a OR t2.b > t1.a OR t1.a > t1.b;
|
|
a b a b
|
|
2 1 NULL NULL
|
|
3 2 3 0
|
|
4 3 4 1
|
|
6 5 6 4
|
|
7 8 7 5
|
|
8 7 NULL NULL
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE NOT(t1.a != t2.a AND t1.a BETWEEN t2.b AND t1.b);
|
|
a b a b
|
|
2 1 NULL NULL
|
|
3 2 3 0
|
|
4 3 4 1
|
|
6 5 6 4
|
|
7 8 7 5
|
|
8 7 NULL NULL
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE t1.a = t2.a AND (t2.b > t1.a OR t1.a > t1.b);
|
|
a b a b
|
|
3 2 3 0
|
|
4 3 4 1
|
|
6 5 6 4
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE NOT(t1.a != t2.a OR t1.a BETWEEN t2.b AND t1.b);
|
|
a b a b
|
|
3 2 3 0
|
|
4 3 4 1
|
|
6 5 6 4
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE t1.a = t2.a OR t1.a = t2.b;
|
|
a b a b
|
|
3 2 3 0
|
|
4 3 4 1
|
|
6 5 6 4
|
|
7 8 7 5
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE t1.a IN(t2.a, t2.b);
|
|
a b a b
|
|
3 2 3 0
|
|
4 3 4 1
|
|
6 5 6 4
|
|
7 8 7 5
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE NOT(t1.a NOT IN(t2.a, t2.b));
|
|
a b a b
|
|
3 2 3 0
|
|
4 3 4 1
|
|
6 5 6 4
|
|
7 8 7 5
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE t1.a != t1.b AND t1.a != t2.b;
|
|
a b a b
|
|
3 2 3 0
|
|
4 3 4 1
|
|
6 5 6 4
|
|
7 8 7 5
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE t1.a NOT IN(t1.b, t2.b);
|
|
a b a b
|
|
3 2 3 0
|
|
4 3 4 1
|
|
6 5 6 4
|
|
7 8 7 5
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE NOT(t1.a IN(t1.b, t2.b));
|
|
a b a b
|
|
3 2 3 0
|
|
4 3 4 1
|
|
6 5 6 4
|
|
7 8 7 5
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE t2.a != t2.b OR (t1.a != t2.a AND t1.a != t2.b);
|
|
a b a b
|
|
3 2 3 0
|
|
4 3 4 1
|
|
6 5 6 4
|
|
7 8 7 5
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE NOT(t2.a = t2.b AND t1.a IN(t2.a, t2.b));
|
|
a b a b
|
|
3 2 3 0
|
|
4 3 4 1
|
|
6 5 6 4
|
|
7 8 7 5
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE t2.a != t2.b AND t1.a != t1.b AND t1.a != t2.b;
|
|
a b a b
|
|
3 2 3 0
|
|
4 3 4 1
|
|
6 5 6 4
|
|
7 8 7 5
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE NOT(t2.a = t2.b OR t1.a IN(t1.b, t2.b));
|
|
a b a b
|
|
3 2 3 0
|
|
4 3 4 1
|
|
6 5 6 4
|
|
7 8 7 5
|
|
EXPLAIN SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE t1.a = t2.a OR t1.a = t2.b;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 ALL PRIMARY NULL NULL NULL 4
|
|
1 SIMPLE t1 eq_ref PRIMARY PRIMARY 4 test.t2.a 1
|
|
EXPLAIN SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE t1.a IN(t2.a, t2.b);
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 ALL PRIMARY NULL NULL NULL 4 Using where
|
|
1 SIMPLE t1 eq_ref PRIMARY PRIMARY 4 test.t2.a 1
|
|
EXPLAIN SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.a WHERE t1.a > IF(t1.a = t2.b-2, t2.b, t2.b-1);
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t2 ALL PRIMARY NULL NULL NULL 4 Using where
|
|
1 SIMPLE t1 eq_ref PRIMARY PRIMARY 4 test.t2.a 1
|
|
DROP TABLE t1,t2;
|
|
DROP VIEW IF EXISTS v1,v2;
|
|
DROP TABLE IF EXISTS t1,t2;
|
|
CREATE TABLE t1 (a int);
|
|
CREATE table t2 (b int);
|
|
INSERT INTO t1 VALUES (1), (2), (3), (4), (1), (1), (3);
|
|
INSERT INTO t2 VALUES (2), (3);
|
|
CREATE VIEW v1 AS SELECT a FROM t1 JOIN t2 ON t1.a=t2.b;
|
|
CREATE VIEW v2 AS SELECT b FROM t2 JOIN t1 ON t2.b=t1.a;
|
|
SELECT v1.a, v2. b
|
|
FROM v1 LEFT OUTER JOIN v2 ON (v1.a=v2.b) AND (v1.a >= 3)
|
|
GROUP BY v1.a;
|
|
a b
|
|
2 NULL
|
|
3 3
|
|
SELECT v1.a, v2. b
|
|
FROM { OJ v1 LEFT OUTER JOIN v2 ON (v1.a=v2.b) AND (v1.a >= 3) }
|
|
GROUP BY v1.a;
|
|
a b
|
|
2 NULL
|
|
3 3
|
|
DROP VIEW v1,v2;
|
|
DROP TABLE t1,t2;
|
|
CREATE TABLE t1 (a int);
|
|
CREATE TABLE t2 (b int);
|
|
INSERT INTO t1 VALUES (1), (2), (3), (4);
|
|
INSERT INTO t2 VALUES (2), (3);
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.b WHERE (1=1);
|
|
a b
|
|
1 NULL
|
|
2 2
|
|
3 3
|
|
4 NULL
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.b WHERE (1 OR 1);
|
|
a b
|
|
1 NULL
|
|
2 2
|
|
3 3
|
|
4 NULL
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.b WHERE (0 OR 1);
|
|
a b
|
|
1 NULL
|
|
2 2
|
|
3 3
|
|
4 NULL
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.b WHERE (1=1 OR 2=2);
|
|
a b
|
|
1 NULL
|
|
2 2
|
|
3 3
|
|
4 NULL
|
|
SELECT * FROM t1 LEFT JOIN t2 ON t1.a = t2.b WHERE (1=1 OR 1=0);
|
|
a b
|
|
1 NULL
|
|
2 2
|
|
3 3
|
|
4 NULL
|
|
DROP TABLE t1,t2;
|
|
CREATE TABLE t1 (
|
|
f1 varchar(16) collate latin1_swedish_ci PRIMARY KEY,
|
|
f2 varchar(16) collate latin1_swedish_ci
|
|
);
|
|
CREATE TABLE t2 (
|
|
f1 varchar(16) collate latin1_swedish_ci PRIMARY KEY,
|
|
f3 varchar(16) collate latin1_swedish_ci
|
|
);
|
|
INSERT INTO t1 VALUES ('bla','blah');
|
|
INSERT INTO t2 VALUES ('bla','sheep');
|
|
SELECT * FROM t1 JOIN t2 USING(f1) WHERE f1='Bla';
|
|
f1 f2 f3
|
|
bla blah sheep
|
|
SELECT * FROM t1 LEFT JOIN t2 USING(f1) WHERE f1='bla';
|
|
f1 f2 f3
|
|
bla blah sheep
|
|
SELECT * FROM t1 LEFT JOIN t2 USING(f1) WHERE f1='Bla';
|
|
f1 f2 f3
|
|
bla blah sheep
|
|
DROP TABLE t1,t2;
|
|
CREATE TABLE t1 (id int PRIMARY KEY, a varchar(8));
|
|
CREATE TABLE t2 (id int NOT NULL, b int NOT NULL, INDEX idx(id));
|
|
INSERT INTO t1 VALUES
|
|
(1,'aaaaaaa'), (5,'eeeeeee'), (4,'ddddddd'), (2,'bbbbbbb'), (3,'ccccccc');
|
|
INSERT INTO t2 VALUES
|
|
(3,10), (2,20), (5,30), (3,20), (5,10), (3,40), (3,30), (2,10), (2,40);
|
|
EXPLAIN
|
|
SELECT t1.id, a FROM t1 LEFT JOIN t2 ON t1.id=t2.id 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 idx idx 4 test.t1.id 2 Using where; Not exists
|
|
flush status;
|
|
SELECT t1.id, a FROM t1 LEFT JOIN t2 ON t1.id=t2.id WHERE t2.b IS NULL;
|
|
id a
|
|
1 aaaaaaa
|
|
4 ddddddd
|
|
show status like 'Handler_read%';
|
|
Variable_name Value
|
|
Handler_read_first 0
|
|
Handler_read_key 5
|
|
Handler_read_next 0
|
|
Handler_read_prev 0
|
|
Handler_read_rnd 0
|
|
Handler_read_rnd_next 6
|
|
DROP TABLE t1,t2;
|
|
CREATE TABLE t1 (c int PRIMARY KEY, e int NOT NULL);
|
|
INSERT INTO t1 VALUES (1,0), (2,1);
|
|
CREATE TABLE t2 (d int PRIMARY KEY);
|
|
INSERT INTO t2 VALUES (1), (2), (3);
|
|
EXPLAIN SELECT * FROM t1 LEFT JOIN t2 ON e<>0 WHERE c=1 AND d IS NULL;
|
|
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 index NULL PRIMARY 4 NULL 3 Using where; Using index; Not exists
|
|
SELECT * FROM t1 LEFT JOIN t2 ON e<>0 WHERE c=1 AND d IS NULL;
|
|
c e d
|
|
1 0 NULL
|
|
SELECT * FROM t1 LEFT JOIN t2 ON e<>0 WHERE c=1 AND d<=>NULL;
|
|
c e d
|
|
1 0 NULL
|
|
DROP TABLE t1,t2;
|