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	Before this fix, the ha_read_last_count status variable was defined and updated internally, for never exposed as a system variable. This fix exposes the system variable as "Handler_read_last", for completness of the Handler_read_* system variables interface. Adjusted tests results accordingly.
		
			
				
	
	
		
			451 lines
		
	
	
		
			15 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			451 lines
		
	
	
		
			15 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| 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),
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| ('9d9aad7764b5b2c53004348ef8d34500',2315652, 3);
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| INSERT INTO t2 (order_id, product_id, product_type) VALUES
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| ('9d9aad7764b5b2c53004348ef8d34500',2315652, 3);
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| select t1.* from t1
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| left join t2 using(order_id, product_id, product_type)
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| where t2.order_id=NULL;
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| order_id	product_id	product_type
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| select t1.* from t1
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| left join t2 using(order_id, product_id, product_type)
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| where t2.order_id is NULL;
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| order_id	product_id	product_type
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| 3d7ce39b5d4b3e3d22aaafe9b633de51	1206029	3
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| 3d7ce39b5d4b3e3d22aaafe9b633de51	5880836	3
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| drop table t1,t2;
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| create table t1 (id int);
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| insert into t1 values (null), (0);
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| create table t2 (id int);
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| insert into t2 values (null);
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| select * from t1, t2 where t1.id = t2.id;
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| id	id
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| alter table t1 add key id (id);
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| select * from t1, t2 where t1.id = t2.id;
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| id	id
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| drop table t1,t2;
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| create table t1 (
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| id  integer,
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| id2 integer not null,
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| index (id),
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| index (id2)
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| );
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| insert into t1 values(null,null),(1,1);
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| Warnings:
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| Warning	1048	Column 'id2' cannot be null
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| select * from t1;
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| id	id2
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| NULL	0
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| 1	1
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| select * from t1 where id <=> null;
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| id	id2
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| NULL	0
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| select * from t1 where id <=> null or id > 0;
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| id	id2
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| NULL	0
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| 1	1
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| select * from t1 where id is null or id > 0;
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| id	id2
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| NULL	0
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| 1	1
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| select * from t1 where id2 <=> null or id2 > 0;
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| id	id2
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| 1	1
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| select * from t1 where id2 is null or id2 > 0;
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| id	id2
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| 1	1
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| delete from t1 where id <=> NULL;
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| select * from t1;
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| id	id2
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| 1	1
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| drop table t1;
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| CREATE TABLE t1 (a int);
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| CREATE TABLE t2 (a int, b int, INDEX idx(a));
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| CREATE TABLE t3 (b int, INDEX idx(b));
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| CREATE TABLE t4 (b int, INDEX idx(b));
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| INSERT INTO t1 VALUES (1), (2), (3), (4);
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| INSERT INTO t2 VALUES (1, 1), (3, 1);
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| INSERT INTO t3 VALUES 
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| (NULL), (NULL), (NULL), (NULL), (NULL),
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| (NULL), (NULL), (NULL), (NULL), (NULL);
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| INSERT INTO t4 SELECT * FROM t3;
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| 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_last	0
 | |
| 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
 |