450 lines
15 KiB
Plaintext
450 lines
15 KiB
Plaintext
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drop table if exists t1,t2;
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create table t1 (a int, b int not null,unique key (a,b),index(b)) engine=myisam;
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insert ignore into t1 values (1,1),(2,2),(3,3),(4,4),(5,5),(6,6),(null,7),(9,9),(8,8),(7,7),(null,9),(null,9),(6,6);
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explain select * from t1 where a 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 ref a a 5 const 3 Using where; Using index
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explain select * from t1 where a is null and b = 2;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref a,b a 9 const,const 1 Using where; Using index
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explain select * from t1 where a is null and b = 7;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref a,b a 9 const,const 1 Using where; Using index
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explain select * from t1 where a=2 and b = 2;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 const a,b a 9 const,const 1 Using index
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explain select * from t1 where a<=>b limit 2;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL a 9 NULL 12 Using where; Using index
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explain select * from t1 where (a is null or a > 0 and a < 3) and b < 5 limit 3;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range a,b a 9 NULL 3 Using where; Using index
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explain select * from t1 where (a is null or a = 7) and b=7;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref_or_null a,b a 9 const,const 2 Using where; Using index
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explain select * from t1 where (a is null or a = 7) and b=7 order by a;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref_or_null a,b a 9 const,const 2 Using where; Using index; Using filesort
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explain select * from t1 where (a is null and b>a) or a is null and b=7 limit 2;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref a,b a 5 const 3 Using where; Using index
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explain select * from t1 where a is null and b=9 or a is null and b=7 limit 3;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range a,b a 9 NULL 3 Using where; Using index
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explain select * from t1 where a > 1 and a < 3 limit 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 range a a 5 NULL 1 Using where; Using index
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explain select * from t1 where a > 8 and a < 9;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range a a 5 NULL 1 Using where; Using index
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select * from t1 where a is null;
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a b
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NULL 7
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NULL 9
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NULL 9
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select * from t1 where a is null and b = 7;
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a b
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NULL 7
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select * from t1 where a<=>b limit 2;
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a b
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1 1
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2 2
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select * from t1 where (a is null or a > 0 and a < 3) and b < 5 limit 3;
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a b
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1 1
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2 2
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select * from t1 where (a is null or a > 0 and a < 3) and b > 7 limit 3;
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a b
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NULL 9
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NULL 9
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select * from t1 where (a is null or a = 7) and b=7;
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a b
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7 7
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NULL 7
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select * from t1 where a is null and b=9 or a is null and b=7 limit 3;
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a b
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NULL 7
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NULL 9
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NULL 9
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select * from t1 where a > 1 and a < 3 limit 1;
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a b
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2 2
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select * from t1 where a > 8 and a < 9;
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a b
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create table t2 like t1;
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insert into t2 select * from t1;
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alter table t1 modify b blob not null, add c int not null, drop key a, add unique key (a,b(20),c), drop key b, add key (b(10));
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explain select * from t1 where a is null and b = 2;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref a,b a 5 const 3 Using where
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explain select * from t1 where a is null and b = 2 and c=0;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref a,b a 5 const 3 Using where
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explain select * from t1 where a is null and b = 7 and c=0;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref a,b a 5 const 3 Using where
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explain select * from t1 where a=2 and b = 2;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref a,b a 5 const 1 Using where
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explain select * from t1 where a<=>b limit 2;
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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 12 Using where
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explain select * from t1 where (a is null or a > 0 and a < 3) and b < 5 and c=0 limit 3;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range a,b a 5 NULL 5 Using where
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explain select * from t1 where (a is null or a = 7) and b=7 and c=0;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref_or_null a,b a 5 const 4 Using where
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explain select * from t1 where (a is null and b>a) or a is null and b=7 limit 2;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref a,b a 5 const 3 Using where
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explain select * from t1 where a is null and b=9 or a is null and b=7 limit 3;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ref a,b a 5 const 3 Using where
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explain select * from t1 where a > 1 and a < 3 limit 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 range a a 5 NULL 1 Using where
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explain select * from t1 where a is null and b=7 or a > 1 and a < 3 limit 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 range a,b a 5 NULL 4 Using where
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explain select * from t1 where a > 8 and a < 9;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range a a 5 NULL 1 Using where
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explain select * from t1 where b like "6%";
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 range b b 12 NULL 1 Using where
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select * from t1 where a is null;
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a b c
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NULL 7 0
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NULL 9 0
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NULL 9 0
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select * from t1 where a is null and b = 7 and c=0;
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a b c
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NULL 7 0
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select * from t1 where a<=>b limit 2;
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a b c
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1 1 0
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2 2 0
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select * from t1 where (a is null or a > 0 and a < 3) and b < 5 limit 3;
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a b c
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1 1 0
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2 2 0
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select * from t1 where (a is null or a > 0 and a < 3) and b > 7 limit 3;
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a b c
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NULL 9 0
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NULL 9 0
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select * from t1 where (a is null or a = 7) and b=7 and c=0;
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a b c
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7 7 0
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NULL 7 0
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select * from t1 where a is null and b=9 or a is null and b=7 limit 3;
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a b c
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NULL 7 0
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NULL 9 0
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NULL 9 0
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select * from t1 where b like "6%";
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a b c
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6 6 0
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drop table t1;
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rename table t2 to t1;
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alter table t1 modify b int null;
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insert into t1 values (7,null), (8,null), (8,7);
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explain select * from t1 where a = 7 and (b=7 or b 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 ref_or_null a,b a 10 const,const 2 Using where; Using index
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select * from t1 where a = 7 and (b=7 or b is null);
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a b
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7 7
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7 NULL
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explain select * from t1 where (a = 7 or a is null) and (b=7 or b 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 ref_or_null a,b a 5 const 4 Using where; Using index
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select * from t1 where (a = 7 or a is null) and (b=7 or b is null);
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a b
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7 NULL
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7 7
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NULL 7
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explain select * from t1 where (a = 7 or a is null) and (a = 7 or a 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 ref_or_null a a 5 const 5 Using where; Using index
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select * from t1 where (a = 7 or a is null) and (a = 7 or a is null);
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a b
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7 NULL
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7 7
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NULL 7
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NULL 9
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NULL 9
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create table t2 (a int);
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insert into t2 values (7),(8);
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explain select * from t2 straight_join t1 where t1.a=t2.a and b 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 t2 ALL NULL NULL NULL NULL 2
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1 SIMPLE t1 ref a,b a 10 test.t2.a,const 2 Using where; Using index
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drop index b on t1;
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explain select * from t2,t1 where t1.a=t2.a and b 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 t2 ALL NULL NULL NULL NULL 2
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1 SIMPLE t1 ref a a 10 test.t2.a,const 2 Using where; Using index
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select * from t2,t1 where t1.a=t2.a and b is null;
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a a b
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7 7 NULL
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8 8 NULL
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explain select * from t2,t1 where t1.a=t2.a and (b= 7 or b 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 t2 ALL NULL NULL NULL NULL 2
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1 SIMPLE t1 ref_or_null a a 10 test.t2.a,const 4 Using where; Using index
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select * from t2,t1 where t1.a=t2.a and (b= 7 or b is null);
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a a b
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7 7 7
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7 7 NULL
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8 8 7
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8 8 NULL
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explain select * from t2,t1 where (t1.a=t2.a or t1.a is null) and b= 7;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t2 ALL NULL NULL NULL NULL 2
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1 SIMPLE t1 ref_or_null a a 10 test.t2.a,const 4 Using where; Using index
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select * from t2,t1 where (t1.a=t2.a or t1.a is null) and b= 7;
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a a b
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7 7 7
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7 NULL 7
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8 8 7
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8 NULL 7
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explain select * from t2,t1 where (t1.a=t2.a or t1.a is null) and (b= 7 or b 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 t2 ALL NULL NULL NULL NULL 2
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1 SIMPLE t1 ref_or_null a a 5 test.t2.a 4 Using where; Using index
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select * from t2,t1 where (t1.a=t2.a or t1.a is null) and (b= 7 or b is null);
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a a b
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7 7 NULL
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7 7 7
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7 NULL 7
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8 8 NULL
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8 8 7
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8 NULL 7
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insert into t2 values (null),(6);
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delete from t1 where a=8;
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explain select * from t2,t1 where t1.a=t2.a or t1.a 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 t2 ALL NULL NULL NULL NULL 4
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1 SIMPLE t1 ref_or_null a a 5 test.t2.a 4 Using where; Using index
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explain select * from t2,t1 where t1.a<=>t2.a or (t1.a is null and t1.b <> 9);
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t2 ALL NULL NULL NULL NULL 4
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1 SIMPLE t1 ref_or_null a a 5 test.t2.a 4 Using where; Using index
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select * from t2,t1 where t1.a<=>t2.a or (t1.a is null and t1.b <> 9);
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a a b
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7 7 NULL
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7 7 7
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7 NULL 7
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8 NULL 7
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NULL NULL 7
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NULL NULL 9
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NULL NULL 9
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6 6 6
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6 NULL 7
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drop table t1,t2;
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CREATE TABLE t1 (
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id int(10) unsigned NOT NULL auto_increment,
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uniq_id int(10) unsigned default NULL,
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PRIMARY KEY (id),
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UNIQUE KEY idx1 (uniq_id)
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) ENGINE=MyISAM;
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CREATE TABLE t2 (
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id int(10) unsigned NOT NULL auto_increment,
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uniq_id int(10) unsigned default NULL,
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PRIMARY KEY (id)
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) ENGINE=MyISAM;
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INSERT INTO t1 VALUES (1,NULL),(2,NULL),(3,1),(4,2),(5,NULL),(6,NULL),(7,3),(8,4),(9,NULL),(10,NULL);
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INSERT INTO t2 VALUES (1,NULL),(2,NULL),(3,1),(4,2),(5,NULL),(6,NULL),(7,3),(8,4),(9,NULL),(10,NULL);
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explain select id from t1 where uniq_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 ref idx1 idx1 5 const 5 Using where
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explain select id from t1 where uniq_id =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 const idx1 idx1 5 const 1
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UPDATE t1 SET id=id+100 where uniq_id is null;
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UPDATE t2 SET id=id+100 where uniq_id is null;
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select id from t1 where uniq_id is null;
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id
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101
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102
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105
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106
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109
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110
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select id from t2 where uniq_id is null;
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id
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101
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102
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105
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106
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109
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110
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DELETE FROM t1 WHERE uniq_id IS NULL;
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DELETE FROM t2 WHERE uniq_id IS NULL;
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SELECT * FROM t1 ORDER BY uniq_id, id;
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id uniq_id
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3 1
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4 2
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7 3
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8 4
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SELECT * FROM t2 ORDER BY uniq_id, id;
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id uniq_id
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3 1
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4 2
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7 3
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8 4
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DROP table t1,t2;
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CREATE TABLE `t1` (
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`order_id` char(32) NOT NULL default '',
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`product_id` char(32) NOT NULL default '',
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`product_type` int(11) NOT NULL default '0',
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PRIMARY KEY (`order_id`,`product_id`,`product_type`)
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) ENGINE=MyISAM;
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CREATE TABLE `t2` (
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`order_id` char(32) NOT NULL default '',
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`product_id` char(32) NOT NULL default '',
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`product_type` int(11) NOT NULL default '0',
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PRIMARY KEY (`order_id`,`product_id`,`product_type`)
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) ENGINE=MyISAM;
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INSERT INTO t1 (order_id, product_id, product_type) VALUES
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('3d7ce39b5d4b3e3d22aaafe9b633de51',1206029, 3),
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('3d7ce39b5d4b3e3d22aaafe9b633de51',5880836, 3),
|
||
|
|
('9d9aad7764b5b2c53004348ef8d34500',2315652, 3);
|
||
|
|
INSERT INTO t2 (order_id, product_id, product_type) VALUES
|
||
|
|
('9d9aad7764b5b2c53004348ef8d34500',2315652, 3);
|
||
|
|
select t1.* from t1
|
||
|
|
left join t2 using(order_id, product_id, product_type)
|
||
|
|
where t2.order_id=NULL;
|
||
|
|
order_id product_id product_type
|
||
|
|
select t1.* from t1
|
||
|
|
left join t2 using(order_id, product_id, product_type)
|
||
|
|
where t2.order_id is NULL;
|
||
|
|
order_id product_id product_type
|
||
|
|
3d7ce39b5d4b3e3d22aaafe9b633de51 1206029 3
|
||
|
|
3d7ce39b5d4b3e3d22aaafe9b633de51 5880836 3
|
||
|
|
drop table t1,t2;
|
||
|
|
create table t1 (id int);
|
||
|
|
insert into t1 values (null), (0);
|
||
|
|
create table t2 (id int);
|
||
|
|
insert into t2 values (null);
|
||
|
|
select * from t1, t2 where t1.id = t2.id;
|
||
|
|
id id
|
||
|
|
alter table t1 add key id (id);
|
||
|
|
select * from t1, t2 where t1.id = t2.id;
|
||
|
|
id id
|
||
|
|
drop table t1,t2;
|
||
|
|
create table t1 (
|
||
|
|
id integer,
|
||
|
|
id2 integer not null,
|
||
|
|
index (id),
|
||
|
|
index (id2)
|
||
|
|
);
|
||
|
|
insert into t1 values(null,null),(1,1);
|
||
|
|
Warnings:
|
||
|
|
Warning 1048 Column 'id2' cannot be null
|
||
|
|
select * from t1;
|
||
|
|
id id2
|
||
|
|
NULL 0
|
||
|
|
1 1
|
||
|
|
select * from t1 where id <=> null;
|
||
|
|
id id2
|
||
|
|
NULL 0
|
||
|
|
select * from t1 where id <=> null or id > 0;
|
||
|
|
id id2
|
||
|
|
NULL 0
|
||
|
|
1 1
|
||
|
|
select * from t1 where id is null or id > 0;
|
||
|
|
id id2
|
||
|
|
NULL 0
|
||
|
|
1 1
|
||
|
|
select * from t1 where id2 <=> null or id2 > 0;
|
||
|
|
id id2
|
||
|
|
1 1
|
||
|
|
select * from t1 where id2 is null or id2 > 0;
|
||
|
|
id id2
|
||
|
|
1 1
|
||
|
|
delete from t1 where id <=> NULL;
|
||
|
|
select * from t1;
|
||
|
|
id id2
|
||
|
|
1 1
|
||
|
|
drop table t1;
|
||
|
|
CREATE TABLE t1 (a int);
|
||
|
|
CREATE TABLE t2 (a int, b int, INDEX idx(a));
|
||
|
|
CREATE TABLE t3 (b int, INDEX idx(b));
|
||
|
|
CREATE TABLE t4 (b int, INDEX idx(b));
|
||
|
|
INSERT INTO t1 VALUES (1), (2), (3), (4);
|
||
|
|
INSERT INTO t2 VALUES (1, 1), (3, 1);
|
||
|
|
INSERT INTO t3 VALUES
|
||
|
|
(NULL), (NULL), (NULL), (NULL), (NULL),
|
||
|
|
(NULL), (NULL), (NULL), (NULL), (NULL);
|
||
|
|
INSERT INTO t4 SELECT * FROM t3;
|
||
|
|
INSERT INTO t3 SELECT * FROM t4;
|
||
|
|
INSERT INTO t4 SELECT * FROM t3;
|
||
|
|
INSERT INTO t3 SELECT * FROM t4;
|
||
|
|
INSERT INTO t4 SELECT * FROM t3;
|
||
|
|
INSERT INTO t3 SELECT * FROM t4;
|
||
|
|
INSERT INTO t4 SELECT * FROM t3;
|
||
|
|
INSERT INTO t3 SELECT * FROM t4;
|
||
|
|
INSERT INTO t4 SELECT * FROM t3;
|
||
|
|
INSERT INTO t3 SELECT * FROM t4;
|
||
|
|
INSERT INTO t4 SELECT * FROM t3;
|
||
|
|
INSERT INTO t3 SELECT * FROM t4;
|
||
|
|
INSERT INTO t4 SELECT * FROM t3;
|
||
|
|
INSERT INTO t3 SELECT * FROM t4;
|
||
|
|
INSERT INTO t4 SELECT * FROM t3;
|
||
|
|
INSERT INTO t3 SELECT * FROM t4;
|
||
|
|
INSERT INTO t3 VALUES (2), (3);
|
||
|
|
ANALYZE table t1, t2, t3;
|
||
|
|
Table Op Msg_type Msg_text
|
||
|
|
test.t1 analyze status OK
|
||
|
|
test.t2 analyze status OK
|
||
|
|
test.t3 analyze status OK
|
||
|
|
SELECT COUNT(*) FROM t3;
|
||
|
|
COUNT(*)
|
||
|
|
15972
|
||
|
|
EXPLAIN SELECT SQL_CALC_FOUND_ROWS * FROM t1 LEFT JOIN t2 ON t1.a=t2.a
|
||
|
|
LEFT JOIN t3 ON t2.b=t3.b;
|
||
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
||
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
|
||
|
|
1 SIMPLE t2 ref idx idx 5 test.t1.a 1
|
||
|
|
1 SIMPLE t3 ref idx idx 5 test.t2.b 1 Using index
|
||
|
|
FLUSH STATUS ;
|
||
|
|
SELECT SQL_CALC_FOUND_ROWS * FROM t1 LEFT JOIN t2 ON t1.a=t2.a
|
||
|
|
LEFT JOIN t3 ON t2.b=t3.b;
|
||
|
|
a a b b
|
||
|
|
1 1 1 NULL
|
||
|
|
2 NULL NULL NULL
|
||
|
|
3 3 1 NULL
|
||
|
|
4 NULL NULL NULL
|
||
|
|
SELECT FOUND_ROWS();
|
||
|
|
FOUND_ROWS()
|
||
|
|
4
|
||
|
|
SHOW STATUS LIKE "handler_read%";
|
||
|
|
Variable_name Value
|
||
|
|
Handler_read_first 0
|
||
|
|
Handler_read_key 6
|
||
|
|
Handler_read_next 2
|
||
|
|
Handler_read_prev 0
|
||
|
|
Handler_read_rnd 0
|
||
|
|
Handler_read_rnd_next 5
|
||
|
|
DROP TABLE t1,t2,t3,t4;
|
||
|
|
CREATE TABLE t1 (
|
||
|
|
a int(11) default NULL,
|
||
|
|
b int(11) default NULL,
|
||
|
|
KEY a (a,b)
|
||
|
|
);
|
||
|
|
INSERT INTO t1 VALUES (0,10),(0,11),(0,12);
|
||
|
|
CREATE TABLE t2 (
|
||
|
|
a int(11) default NULL,
|
||
|
|
b int(11) default NULL,
|
||
|
|
KEY a (a)
|
||
|
|
);
|
||
|
|
INSERT INTO t2 VALUES (3,NULL),(3,11),(3,12);
|
||
|
|
SELECT * FROM t2 inner join t1 WHERE ( t1.a = 0 OR t1.a IS NULL) AND t2.a = 3 AND t2.b = t1.b;
|
||
|
|
a b a b
|
||
|
|
3 11 0 11
|
||
|
|
3 12 0 12
|
||
|
|
drop table t1, t2;
|
||
|
|
End of 5.0 tests
|