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90484de3f7
constant outer tables did not return null complemented rows when conditions were evaluated to FALSE. Wrong results were returned because the conditions over constant outer tables, when being pushed down, were erroneously enclosed into the guard function used for WHERE conditions. mysql-test/r/join_outer.result: Added a test case for bug #28571. mysql-test/t/join_outer.test: Added a test case for bug #28571. sql/sql_select.cc: Fixed bug #28571. Outer join queries with ON conditions over constant outer tables did not return null complemented rows when conditions were evaluated to FALSE. Wrong results were returned because the conditions over constant outer tables, when being pushed down, were erroneously enclosed into the guard function used for WHERE conditions. The problem is fixed in the function make_join_select. Now the conditions over constant tables from ON expressions are pushed down after the conditions from WHERE has been pushed down.
1256 lines
40 KiB
Text
1256 lines
40 KiB
Text
drop table if exists t0,t1,t2,t3,t4,t5;
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CREATE TABLE t1 (
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grp int(11) default NULL,
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a bigint(20) unsigned default NULL,
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c char(10) NOT NULL default ''
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) ENGINE=MyISAM;
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INSERT INTO t1 VALUES (1,1,'a'),(2,2,'b'),(2,3,'c'),(3,4,'E'),(3,5,'C'),(3,6,'D'),(NULL,NULL,'');
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create table t2 (id int, a bigint unsigned not null, c char(10), d int, primary key (a));
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insert into t2 values (1,1,"a",1),(3,4,"A",4),(3,5,"B",5),(3,6,"C",6),(4,7,"D",7);
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select t1.*,t2.* from t1 JOIN t2 where t1.a=t2.a;
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grp a c id a c d
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1 1 a 1 1 a 1
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3 4 E 3 4 A 4
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3 5 C 3 5 B 5
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3 6 D 3 6 C 6
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select t1.*,t2.* from t1 left join t2 on (t1.a=t2.a) order by t1.grp,t1.a,t2.c;
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grp a c id a c d
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NULL NULL NULL NULL NULL NULL
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1 1 a 1 1 a 1
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2 2 b NULL NULL NULL NULL
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2 3 c NULL NULL NULL NULL
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3 4 E 3 4 A 4
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3 5 C 3 5 B 5
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3 6 D 3 6 C 6
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select t1.*,t2.* from { oj t2 left outer join t1 on (t1.a=t2.a) };
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grp a c id a c d
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1 1 a 1 1 a 1
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3 4 E 3 4 A 4
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3 5 C 3 5 B 5
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3 6 D 3 6 C 6
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NULL NULL NULL 4 7 D 7
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select t1.*,t2.* from t1 as t0,{ oj t2 left outer join t1 on (t1.a=t2.a) } WHERE t0.a=2;
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grp a c id a c d
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1 1 a 1 1 a 1
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3 4 E 3 4 A 4
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3 5 C 3 5 B 5
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3 6 D 3 6 C 6
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NULL NULL NULL 4 7 D 7
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select t1.*,t2.* from t1 left join t2 using (a);
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grp a c id a c d
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1 1 a 1 1 a 1
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2 2 b NULL NULL NULL NULL
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2 3 c NULL NULL NULL NULL
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3 4 E 3 4 A 4
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3 5 C 3 5 B 5
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3 6 D 3 6 C 6
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NULL NULL NULL NULL NULL NULL
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select t1.*,t2.* from t1 left join t2 using (a) where t1.a=t2.a;
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grp a c id a c d
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1 1 a 1 1 a 1
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3 4 E 3 4 A 4
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3 5 C 3 5 B 5
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3 6 D 3 6 C 6
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select t1.*,t2.* from t1 left join t2 using (a,c);
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grp a c id a c d
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1 1 a 1 1 a 1
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2 2 b NULL NULL NULL NULL
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2 3 c NULL NULL NULL NULL
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3 4 E NULL NULL NULL NULL
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3 5 C NULL NULL NULL NULL
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3 6 D NULL NULL NULL NULL
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NULL NULL NULL NULL NULL NULL
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select t1.*,t2.* from t1 left join t2 using (c);
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grp a c id a c d
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1 1 a 1 1 a 1
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1 1 a 3 4 A 4
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2 2 b 3 5 B 5
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2 3 c 3 6 C 6
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3 4 E NULL NULL NULL NULL
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3 5 C 3 6 C 6
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3 6 D 4 7 D 7
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NULL NULL NULL NULL NULL NULL
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select t1.*,t2.* from t1 natural left outer join t2;
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grp a c id a c d
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1 1 a 1 1 a 1
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2 2 b NULL NULL NULL NULL
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2 3 c NULL NULL NULL NULL
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3 4 E NULL NULL NULL NULL
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3 5 C NULL NULL NULL NULL
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3 6 D NULL NULL NULL NULL
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NULL NULL NULL NULL NULL NULL
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select t1.*,t2.* from t1 left join t2 on (t1.a=t2.a) where t2.id=3;
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grp a c id a c d
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3 4 E 3 4 A 4
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3 5 C 3 5 B 5
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3 6 D 3 6 C 6
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select t1.*,t2.* from t1 left join t2 on (t1.a=t2.a) where t2.id is null;
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grp a c id a c d
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2 2 b NULL NULL NULL NULL
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2 3 c NULL NULL NULL NULL
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NULL NULL NULL NULL NULL NULL
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explain select t1.*,t2.* from t1,t2 where t1.a=t2.a and isnull(t2.a)=1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
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explain select t1.*,t2.* from t1 left join t2 on t1.a=t2.a where isnull(t2.a)=1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 7
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1 SIMPLE t2 eq_ref PRIMARY PRIMARY 8 test.t1.a 1 Using where
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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);
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grp a c id a c d a
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1 1 a 1 1 a 1 1
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2 2 b NULL NULL NULL NULL NULL
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2 3 c NULL NULL NULL NULL NULL
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3 4 E 3 4 A 4 4
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3 5 C 3 5 B 5 5
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3 6 D 3 6 C 6 6
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NULL NULL NULL NULL NULL NULL NULL
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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);
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ERROR 42S22: Unknown column 't3.a' in 'on clause'
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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);
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ERROR 42S22: Unknown column 't3.a' in 'on clause'
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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);
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ERROR 42S22: Unknown column 't3.a' in 'on clause'
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select t1.*,t2.* from t1 inner join t2 using (a);
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grp a c id a c d
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1 1 a 1 1 a 1
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3 4 E 3 4 A 4
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3 5 C 3 5 B 5
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3 6 D 3 6 C 6
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select t1.*,t2.* from t1 inner join t2 on (t1.a=t2.a);
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grp a c id a c d
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1 1 a 1 1 a 1
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3 4 E 3 4 A 4
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3 5 C 3 5 B 5
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3 6 D 3 6 C 6
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select t1.*,t2.* from t1 natural join t2;
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grp a c id a c d
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1 1 a 1 1 a 1
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drop table t1,t2;
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CREATE TABLE t1 (
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usr_id INT unsigned NOT NULL,
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uniq_id INT unsigned NOT NULL AUTO_INCREMENT,
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start_num INT unsigned NOT NULL DEFAULT 1,
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increment INT unsigned NOT NULL DEFAULT 1,
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PRIMARY KEY (uniq_id),
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INDEX usr_uniq_idx (usr_id, uniq_id),
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INDEX uniq_usr_idx (uniq_id, usr_id)
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);
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CREATE TABLE t2 (
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id INT unsigned NOT NULL DEFAULT 0,
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usr2_id INT unsigned NOT NULL DEFAULT 0,
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max INT unsigned NOT NULL DEFAULT 0,
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c_amount INT unsigned NOT NULL DEFAULT 0,
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d_max INT unsigned NOT NULL DEFAULT 0,
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d_num INT unsigned NOT NULL DEFAULT 0,
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orig_time INT unsigned NOT NULL DEFAULT 0,
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c_time INT unsigned NOT NULL DEFAULT 0,
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active ENUM ("no","yes") NOT NULL,
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PRIMARY KEY (id,usr2_id),
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INDEX id_idx (id),
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INDEX usr2_idx (usr2_id)
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);
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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);
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SELECT t1.usr_id,t1.uniq_id,t1.increment,
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t2.usr2_id,t2.c_amount,t2.max
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FROM t1
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LEFT JOIN t2 ON t2.id = t1.uniq_id
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WHERE t1.uniq_id = 4
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ORDER BY t2.c_amount;
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usr_id uniq_id increment usr2_id c_amount max
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3 4 84676 NULL NULL NULL
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SELECT t1.usr_id,t1.uniq_id,t1.increment,
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t2.usr2_id,t2.c_amount,t2.max
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FROM t2
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RIGHT JOIN t1 ON t2.id = t1.uniq_id
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WHERE t1.uniq_id = 4
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ORDER BY t2.c_amount;
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usr_id uniq_id increment usr2_id c_amount max
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3 4 84676 NULL NULL NULL
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INSERT INTO t2 VALUES (2,3,3000,6000,0,0,746584,837484,'yes');
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INSERT INTO t2 VALUES (2,3,3000,6000,0,0,746584,837484,'yes');
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ERROR 23000: Duplicate entry '2-3' for key 1
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INSERT INTO t2 VALUES (7,3,1000,2000,0,0,746294,937484,'yes');
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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;
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usr_id uniq_id increment usr2_id c_amount max
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3 4 84676 NULL NULL NULL
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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;
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usr_id uniq_id increment usr2_id c_amount max
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3 4 84676 NULL NULL NULL
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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;
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usr_id uniq_id increment usr2_id c_amount max
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3 4 84676 NULL NULL NULL
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drop table t1,t2;
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CREATE TABLE t1 (
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cod_asig int(11) DEFAULT '0' NOT NULL,
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desc_larga_cat varchar(80) DEFAULT '' NOT NULL,
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desc_larga_cas varchar(80) DEFAULT '' NOT NULL,
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desc_corta_cat varchar(40) DEFAULT '' NOT NULL,
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desc_corta_cas varchar(40) DEFAULT '' NOT NULL,
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cred_total double(3,1) DEFAULT '0.0' NOT NULL,
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pre_requisit int(11),
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co_requisit int(11),
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preco_requisit int(11),
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PRIMARY KEY (cod_asig)
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);
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INSERT INTO t1 VALUES (10360,'asdfggfg','Introduccion a los Ordenadores I','asdfggfg','Introduccio Ordinadors I',6.0,NULL,NULL,NULL);
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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);
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INSERT INTO t1 VALUES (10362,'Laboratori d`Ordinadors','Laboratorio de Ordenadores','Laboratori d`Ordinadors','Laboratori Ordinadors',4.5,NULL,NULL,NULL);
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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);
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INSERT INTO t1 VALUES (11403,'Projecte Fi de Carrera','Proyecto Fin de Carrera','Projecte Fi de Carrera','PFC',9.0,NULL,NULL,NULL);
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INSERT INTO t1 VALUES (11404,'+lgebra lineal','Algebra lineal','+lgebra lineal','+lgebra lineal',15.0,NULL,NULL,NULL);
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INSERT INTO t1 VALUES (11405,'+lgebra lineal','Algebra lineal','+lgebra lineal','+lgebra lineal',18.0,NULL,NULL,NULL);
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INSERT INTO t1 VALUES (11406,'Calcul Infinitesimal','Cßlculo Infinitesimal','Calcul Infinitesimal','Calcul Infinitesimal',15.0,NULL,NULL,NULL);
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CREATE TABLE t2 (
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idAssignatura int(11) DEFAULT '0' NOT NULL,
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Grup int(11) DEFAULT '0' NOT NULL,
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Places smallint(6) DEFAULT '0' NOT NULL,
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PlacesOcupades int(11) DEFAULT '0',
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PRIMARY KEY (idAssignatura,Grup)
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);
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INSERT INTO t2 VALUES (10360,12,333,0);
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INSERT INTO t2 VALUES (10361,30,2,0);
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INSERT INTO t2 VALUES (10361,40,3,0);
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INSERT INTO t2 VALUES (10360,45,10,0);
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INSERT INTO t2 VALUES (10362,10,12,0);
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INSERT INTO t2 VALUES (10360,55,2,0);
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INSERT INTO t2 VALUES (10360,70,0,0);
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INSERT INTO t2 VALUES (10360,565656,0,0);
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INSERT INTO t2 VALUES (10360,32767,7,0);
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INSERT INTO t2 VALUES (10360,33,8,0);
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INSERT INTO t2 VALUES (10360,7887,85,0);
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INSERT INTO t2 VALUES (11405,88,8,0);
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INSERT INTO t2 VALUES (10360,0,55,0);
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INSERT INTO t2 VALUES (10360,99,0,0);
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INSERT INTO t2 VALUES (11411,30,10,0);
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INSERT INTO t2 VALUES (11404,0,0,0);
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INSERT INTO t2 VALUES (10362,11,111,0);
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INSERT INTO t2 VALUES (10363,33,333,0);
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INSERT INTO t2 VALUES (11412,55,0,0);
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INSERT INTO t2 VALUES (50003,66,6,0);
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INSERT INTO t2 VALUES (11403,5,0,0);
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INSERT INTO t2 VALUES (11406,11,11,0);
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INSERT INTO t2 VALUES (11410,11410,131,0);
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INSERT INTO t2 VALUES (11416,11416,32767,0);
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INSERT INTO t2 VALUES (11409,0,0,0);
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CREATE TABLE t3 (
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id int(11) NOT NULL auto_increment,
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dni_pasaporte char(16) DEFAULT '' NOT NULL,
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idPla int(11) DEFAULT '0' NOT NULL,
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cod_asig int(11) DEFAULT '0' NOT NULL,
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any smallint(6) DEFAULT '0' NOT NULL,
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quatrimestre smallint(6) DEFAULT '0' NOT NULL,
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estat char(1) DEFAULT 'M' NOT NULL,
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PRIMARY KEY (id),
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UNIQUE dni_pasaporte (dni_pasaporte,idPla),
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UNIQUE dni_pasaporte_2 (dni_pasaporte,idPla,cod_asig,any,quatrimestre)
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);
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INSERT INTO t3 VALUES (1,'11111111',1,10362,98,1,'M');
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CREATE TABLE t4 (
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id int(11) NOT NULL auto_increment,
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papa int(11) DEFAULT '0' NOT NULL,
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fill int(11) DEFAULT '0' NOT NULL,
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idPla int(11) DEFAULT '0' NOT NULL,
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PRIMARY KEY (id),
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KEY papa (idPla,papa),
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UNIQUE papa_2 (idPla,papa,fill)
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);
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INSERT INTO t4 VALUES (1,-1,10360,1);
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INSERT INTO t4 VALUES (2,-1,10361,1);
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INSERT INTO t4 VALUES (3,-1,10362,1);
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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;
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fill desc_larga_cat cred_total Grup Places PlacesOcupades
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10360 asdfggfg 6.0 0 55 0
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10360 asdfggfg 6.0 12 333 0
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10360 asdfggfg 6.0 33 8 0
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10360 asdfggfg 6.0 45 10 0
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10360 asdfggfg 6.0 55 2 0
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10360 asdfggfg 6.0 7887 85 0
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10360 asdfggfg 6.0 32767 7 0
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10361 Components i Circuits Electronics I 6.0 30 2 0
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10361 Components i Circuits Electronics I 6.0 40 3 0
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10362 Laboratori d`Ordinadors 4.5 10 12 0
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10362 Laboratori d`Ordinadors 4.5 11 111 0
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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 ;
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fill idPla
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10360 NULL
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10361 NULL
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10362 NULL
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INSERT INTO t3 VALUES (3,'1234',1,10360,98,1,'S');
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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 ;
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fill idPla
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10360 1
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10361 NULL
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10362 NULL
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drop table t1,t2,t3,test.t4;
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CREATE TABLE t1 (
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id smallint(5) unsigned NOT NULL auto_increment,
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name char(60) DEFAULT '' NOT NULL,
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PRIMARY KEY (id)
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);
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INSERT INTO t1 VALUES (1,'Antonio Paz');
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INSERT INTO t1 VALUES (2,'Lilliana Angelovska');
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INSERT INTO t1 VALUES (3,'Thimble Smith');
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CREATE TABLE t2 (
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id smallint(5) unsigned NOT NULL auto_increment,
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owner smallint(5) unsigned DEFAULT '0' NOT NULL,
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name char(60),
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PRIMARY KEY (id)
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);
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INSERT INTO t2 VALUES (1,1,'El Gato');
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INSERT INTO t2 VALUES (2,1,'Perrito');
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INSERT INTO t2 VALUES (3,3,'Happy');
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select t1.name, t2.name, t2.id from t1 left join t2 on (t1.id = t2.owner);
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name name id
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Antonio Paz El Gato 1
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Antonio Paz Perrito 2
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Lilliana Angelovska NULL NULL
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Thimble Smith Happy 3
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select t1.name, t2.name, t2.id from t1 left join t2 on (t1.id = t2.owner) where t2.id is null;
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name name id
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Lilliana Angelovska NULL NULL
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explain select t1.name, t2.name, t2.id from t1 left join t2 on (t1.id = t2.owner) where t2.id is null;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 3
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1 SIMPLE t2 ALL NULL NULL NULL NULL 3 Using where; Not exists
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explain select t1.name, t2.name, t2.id from t1 left join t2 on (t1.id = t2.owner) where t2.name is null;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 3
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1 SIMPLE t2 ALL NULL NULL NULL NULL 3 Using where
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select count(*) from t1 left join t2 on (t1.id = t2.owner);
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count(*)
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4
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select t1.name, t2.name, t2.id from t2 right join t1 on (t1.id = t2.owner);
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name name id
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Antonio Paz El Gato 1
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Antonio Paz Perrito 2
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Lilliana Angelovska NULL NULL
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Thimble Smith Happy 3
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select t1.name, t2.name, t2.id from t2 right join t1 on (t1.id = t2.owner) where t2.id is null;
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name name id
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Lilliana Angelovska NULL NULL
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explain select t1.name, t2.name, t2.id from t2 right join t1 on (t1.id = t2.owner) where t2.id is null;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 3
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1 SIMPLE t2 ALL NULL NULL NULL NULL 3 Using where; Not exists
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explain select t1.name, t2.name, t2.id from t2 right join t1 on (t1.id = t2.owner) where t2.name is null;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 3
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1 SIMPLE t2 ALL NULL NULL NULL NULL 3 Using where
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select count(*) from t2 right join t1 on (t1.id = t2.owner);
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count(*)
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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;
|