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			387 lines
		
	
	
		
			19 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			387 lines
		
	
	
		
			19 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| drop table if exists t0, t1, t2, t3, t4;
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| create table t0
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| (
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| key1 int not null, 
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| INDEX i1(key1)
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| );
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| alter table t0 add key2 int not null, add index i2(key2);
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| alter table t0 add key3 int not null, add index i3(key3);
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| alter table t0 add key4 int not null, add index i4(key4);
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| alter table t0 add key5 int not null, add index i5(key5);
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| alter table t0 add key6 int not null, add index i6(key6);
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| alter table t0 add key7 int not null, add index i7(key7);
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| alter table t0 add key8 int not null, add index i8(key8);
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| update t0 set key2=key1,key3=key1,key4=key1,key5=key1,key6=key1,key7=key1,key8=1024-key1;
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| analyze table t0;
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| Table	Op	Msg_type	Msg_text
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| test.t0	analyze	status	OK
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| explain select * from t0 where key1 < 3 or key1 > 1020;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	range	i1	i1	4	NULL	78	Using where
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| explain 
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| select * from t0 where key1 < 3 or key2 > 1020;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2	i1,i2	4,4	NULL	45	Using sort_union(i1,i2); Using where
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| select * from t0 where key1 < 3 or key2 > 1020;
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| key1	key2	key3	key4	key5	key6	key7	key8
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| 1	1	1	1	1	1	1	1023
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| 2	2	2	2	2	2	2	1022
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| 1021	1021	1021	1021	1021	1021	1021	3
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| 1022	1022	1022	1022	1022	1022	1022	2
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| 1023	1023	1023	1023	1023	1023	1023	1
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| 1024	1024	1024	1024	1024	1024	1024	0
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| explain select * from t0 where key1 < 3 or key2 <4;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2	i1,i2	4,4	NULL	7	Using sort_union(i1,i2); Using where
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| explain
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| select * from t0 where (key1 > 30 and key1<35) or (key2 >32 and key2 < 40);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2	i1,i2	4,4	NULL	11	Using sort_union(i1,i2); Using where
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| select * from t0 where (key1 > 30 and key1<35) or (key2 >32 and key2 < 40);
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| key1	key2	key3	key4	key5	key6	key7	key8
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| 31	31	31	31	31	31	31	993
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| 32	32	32	32	32	32	32	992
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| 33	33	33	33	33	33	33	991
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| 34	34	34	34	34	34	34	990
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| 35	35	35	35	35	35	35	989
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| 36	36	36	36	36	36	36	988
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| 37	37	37	37	37	37	37	987
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| 38	38	38	38	38	38	38	986
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| 39	39	39	39	39	39	39	985
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| explain select * from t0 ignore index (i2) where key1 < 3 or key2 <4;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	ALL	i1	NULL	NULL	NULL	1024	Using where
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| explain select * from t0 where (key1 < 3 or key2 <4) and key3 = 50;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	ref	i1,i2,i3	i3	4	const	1	Using where
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| explain select * from t0 use index (i1,i2) where (key1 < 3 or key2 <4) and key3 = 50;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2	i1,i2	4,4	NULL	7	Using sort_union(i1,i2); Using where
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| explain select * from t0 where (key1 > 1 or key2  > 2);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	ALL	i1,i2	NULL	NULL	NULL	1024	Using where
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| explain select * from t0 force index (i1,i2) where (key1 > 1 or key2  > 2);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2	i1,i2	4,4	NULL	1024	Using sort_union(i1,i2); Using where
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| explain 
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| select * from t0 where key1<3 or key2<3 or (key1>5 and key1<8) or 
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| (key1>10 and key1<12) or (key2>100 and key2<110);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2	i1,i2	4,4	NULL	17	Using sort_union(i1,i2); Using where
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| explain select * from t0 where key2 = 45 or key1 <=> null;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	range	i1,i2	i2	4	NULL	1	Using where
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| explain select * from t0 where key2 = 45 or key1 is not null;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	ALL	i1,i2	NULL	NULL	NULL	1024	Using where
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| explain select * from t0 where key2 = 45 or key1 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	t0	ref	i2	i2	4	const	1	
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| explain select * from t0 where key2=10 or key3=3 or key4 <=> null;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i2,i3,i4	i2,i3	4,4	NULL	2	Using union(i2,i3); Using where
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| explain select * from t0 where key2=10 or key3=3 or key4 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	t0	index_merge	i2,i3	i2,i3	4,4	NULL	2	Using union(i2,i3); Using where
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| explain select key1 from t0 where (key1 <=> null) or (key2 < 5) or 
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| (key3=10) or (key4 <=> null);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2,i3,i4	i2,i3	4,4	NULL	6	Using sort_union(i2,i3); Using where
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| explain select key1 from t0 where (key1 <=> null) or (key1 < 5) or 
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| (key3=10) or (key4 <=> null);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i3,i4	i1,i3	4,4	NULL	6	Using sort_union(i1,i3); Using where
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| explain select * from t0 where 
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| (key1 < 3 or key2 < 3) and (key3 < 4 or key4 < 4) and (key5 < 5 or key6 < 5);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2,i3,i4,i5,i6	i1,i2	4,4	NULL	6	Using sort_union(i1,i2); Using where
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| explain
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| select * from t0 where (key1 < 3 or key2 < 6) and (key1 < 7 or key3 < 4);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2,i3	i1,i2	4,4	NULL	9	Using sort_union(i1,i2); Using where
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| select * from t0 where (key1 < 3 or key2 < 6) and (key1 < 7 or key3 < 4);
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| key1	key2	key3	key4	key5	key6	key7	key8
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| 1	1	1	1	1	1	1	1023
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| 2	2	2	2	2	2	2	1022
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| 3	3	3	3	3	3	3	1021
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| 4	4	4	4	4	4	4	1020
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| 5	5	5	5	5	5	5	1019
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| explain select * from t0 where 
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| (key1 < 3 or key2 < 3) and (key3 < 4 or key4 < 4) and (key5 < 2 or key6 < 2);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2,i3,i4,i5,i6	i1,i2	4,4	NULL	6	Using sort_union(i1,i2); Using where
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| explain select * from t0 where 
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| (key1 < 3 or key2 < 3) and (key3 < 100);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	range	i1,i2,i3	i3	4	NULL	95	Using where
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| explain select * from t0 where
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| (key1 < 3 or key2 < 3) and (key3 < 1000);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	ALL	i1,i2,i3	NULL	NULL	NULL	1024	Using where
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| explain select * from t0 where 
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| ((key1 < 4 or key2 < 4) and (key2 <5 or key3 < 4)) 
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| or 
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| key2 > 5;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	ALL	i1,i2,i3	NULL	NULL	NULL	1024	Using where
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| explain select * from t0 where
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| ((key1 < 4 or key2 < 4) and (key2 <5 or key3 < 4))
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| or
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| key1 < 7;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2,i3	i1,i2	4,4	NULL	10	Using sort_union(i1,i2); Using where
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| select * from t0 where
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| ((key1 < 4 or key2 < 4) and (key2 <5 or key3 < 4))
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| or
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| key1 < 7;
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| key1	key2	key3	key4	key5	key6	key7	key8
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| 1	1	1	1	1	1	1	1023
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| 2	2	2	2	2	2	2	1022
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| 3	3	3	3	3	3	3	1021
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| 4	4	4	4	4	4	4	1020
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| 5	5	5	5	5	5	5	1019
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| 6	6	6	6	6	6	6	1018
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| explain select * from t0 where 
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| ((key1 < 4 or key2 < 4) and (key3 <5 or key5 < 4)) 
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| or 
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| ((key5 < 5 or key6 < 6) and (key7 <7 or key8 < 4));
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2,i3,i5,i6,i7,i8	i1,i2,i5,i6	4,4,4,4	NULL	19	Using sort_union(i1,i2,i5,i6); Using where
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| explain select * from t0 where
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| ((key3 <5 or key5 < 4) and (key1 < 4 or key2 < 4))
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| or
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| ((key7 <7 or key8 < 4) and (key5 < 5 or key6 < 6));
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2,i3,i5,i6,i7,i8	i3,i5,i7,i8	4,4,4,4	NULL	20	Using sort_union(i3,i5,i7,i8); Using where
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| explain select * from t0 where
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| ((key3 <5 or key5 < 4) and (key1 < 4 or key2 < 4))
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| or
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| ((key3 <7 or key5 < 2) and (key5 < 5 or key6 < 6));
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2,i3,i5,i6	i3,i5	4,4	NULL	11	Using sort_union(i3,i5); Using where
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| explain select * from t0 where
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| ((key3 <5 or key5 < 4) and (key1 < 4 or key2 < 4))
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| or
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| (((key3 <7 and key7 < 6) or key5 < 2) and (key5 < 5 or key6 < 6));
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2,i3,i5,i6,i7	i3,i5	4,4	NULL	11	Using sort_union(i3,i5); Using where
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| explain select * from t0 where
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| ((key3 <5 or key5 < 4) and (key1 < 4 or key2 < 4))
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| or
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| ((key3 >=5 or key5 < 2) and (key5 < 5 or key6 < 6));
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	ALL	i1,i2,i3,i5,i6	NULL	NULL	NULL	1024	Using where
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| explain select * from t0 force index(i1, i2, i3, i4, i5, i6 ) where
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| ((key3 <5 or key5 < 4) and (key1 < 4 or key2 < 4))
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| or
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| ((key3 >=5 or key5 < 2) and (key5 < 5 or key6 < 6));
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2,i3,i5,i6	i3,i5	0,4	NULL	1024	Using sort_union(i3,i5); Using where
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| select * from t0 where key1 < 5 or key8 < 4 order by key1;
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| key1	key2	key3	key4	key5	key6	key7	key8
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| 1	1	1	1	1	1	1	1023
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| 2	2	2	2	2	2	2	1022
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| 3	3	3	3	3	3	3	1021
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| 4	4	4	4	4	4	4	1020
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| 1021	1021	1021	1021	1021	1021	1021	3
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| 1022	1022	1022	1022	1022	1022	1022	2
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| 1023	1023	1023	1023	1023	1023	1023	1
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| 1024	1024	1024	1024	1024	1024	1024	0
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| explain
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| select * from t0 where key1 < 5 or key8 < 4 order by key1;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i8	i1,i8	4,4	NULL	9	Using sort_union(i1,i8); Using where; Using filesort
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| create table t2 like t0;
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| insert into t2 select * from t0;
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| alter table t2 add index i1_3(key1, key3);
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| alter table t2 add index i2_3(key2, key3);
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| alter table t2 drop index i1;
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| alter table t2 drop index i2;
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| alter table t2 add index i321(key3, key2, key1);
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| explain select key3 from t2 where key1 = 100 or key2 = 100;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t2	index_merge	i1_3,i2_3	i1_3,i2_3	4,4	NULL	2	Using sort_union(i1_3,i2_3); Using where
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| explain select key3 from t2 where key1 <100 or key2 < 100;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t2	index	i1_3,i2_3	i321	12	NULL	1024	Using where; Using index
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| explain select key7 from t2 where key1 <100 or key2 < 100;
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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	i1_3,i2_3	NULL	NULL	NULL	1024	Using where
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| create table t4 (
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| key1a int not null,
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| key1b int not null,
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| key2  int not null,
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| key2_1 int not null,
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| key2_2 int not null,
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| key3  int not null,
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| index i1a (key1a, key1b),
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| index i1b (key1b, key1a),
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| index i2_1(key2, key2_1),
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| index i2_2(key2, key2_1)
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| );
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| insert into t4 select key1,key1,key1 div 10, key1 % 10, key1 % 10, key1 from t0;
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| select * from t4 where key1a = 3 or key1b = 4;
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| key1a	key1b	key2	key2_1	key2_2	key3
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| 3	3	0	3	3	3
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| 4	4	0	4	4	4
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| explain select * from t4 where key1a = 3 or key1b = 4;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t4	index_merge	i1a,i1b	i1a,i1b	4,4	NULL	2	Using sort_union(i1a,i1b); Using where
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| explain select * from t4 where key2 = 1 and (key2_1 = 1 or key3 = 5);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t4	ref	i2_1,i2_2	i2_1	4	const	10	Using where
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| explain select * from t4 where key2 = 1 and (key2_1 = 1 or key2_2 = 5);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t4	ref	i2_1,i2_2	i2_1	4	const	10	Using where
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| explain select * from t4 where key2_1 = 1 or key2_2 = 5;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t4	ALL	NULL	NULL	NULL	NULL	1024	Using where
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| create table t1 like t0;
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| insert into t1 select * from t0;
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| explain select * from t0 left join t1 on (t0.key1=t1.key1) 
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| where t0.key1=3 or t0.key2=4;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2	i1,i2	4,4	NULL	2	Using union(i1,i2); Using where
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| 1	SIMPLE	t1	ref	i1	i1	4	test.t0.key1	1	
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| select * from t0 left join t1 on (t0.key1=t1.key1)
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| where t0.key1=3 or t0.key2=4;
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| key1	key2	key3	key4	key5	key6	key7	key8	key1	key2	key3	key4	key5	key6	key7	key8
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| 3	3	3	3	3	3	3	1021	3	3	3	3	3	3	3	1021
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| 4	4	4	4	4	4	4	1020	4	4	4	4	4	4	4	1020
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| explain 
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| select * from t0,t1 where (t0.key1=t1.key1) and ( t0.key1=3 or t0.key2=4);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	index_merge	i1,i2	i1,i2	4,4	NULL	2	Using union(i1,i2); Using where
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| 1	SIMPLE	t1	ref	i1	i1	4	test.t0.key1	1	
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| explain 
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| select * from t0,t1 where (t0.key1=t1.key1) and 
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| (t0.key1=3 or t0.key2=4) and t1.key1<200;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	ALL	i1,i2	NULL	NULL	NULL	1024	Using where
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| 1	SIMPLE	t1	ref	i1	i1	4	test.t0.key1	1	
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| explain 
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| select * from t0,t1 where (t0.key1=t1.key1) and 
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| (t0.key1=3 or t0.key2<4) and t1.key1=2;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	ref	i1,i2	i1	4	const	1	Using where
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| 1	SIMPLE	t1	ref	i1	i1	4	const	1	
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| explain select * from t0,t1 where t0.key1 = 5 and 
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| (t1.key1 = t0.key1 or t1.key8 = t0.key1);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	ref	i1	i1	4	const	1	
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| 1	SIMPLE	t1	index_merge	i1,i8	i1,i8	4,4	NULL	2	Using union(i1,i8); Using where
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| explain select * from t0,t1 where t0.key1 < 3 and
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| (t1.key1 = t0.key1 or t1.key8 = t0.key1);
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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| 1	SIMPLE	t0	range	i1	i1	4	NULL	3	Using where
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| 1	SIMPLE	t1	ALL	i1,i8	NULL	NULL	NULL	1024	Range checked for each record (index map: 0x81)
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| explain select * from t1 where key1=3 or key2=4 
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| union select * from t1 where key1<4 or key3=5;
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| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	PRIMARY	t1	index_merge	i1,i2	i1,i2	4,4	NULL	2	Using union(i1,i2); Using where
 | |
| 2	UNION	t1	index_merge	i1,i3	i1,i3	4,4	NULL	5	Using sort_union(i1,i3); Using where
 | |
| NULL	UNION RESULT	<union1,2>	ALL	NULL	NULL	NULL	NULL	NULL	
 | |
| explain select * from (select * from t1 where key1 = 3 or key2 =3) as Z where key8 >5;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	PRIMARY	<derived2>	system	NULL	NULL	NULL	NULL	1	
 | |
| 2	DERIVED	t1	index_merge	i1,i2	i1,i2	4,4	NULL	2	Using union(i1,i2); Using where
 | |
| create table t3 like t0;
 | |
| insert into t3 select * from t0;
 | |
| alter table t3 add key9 int not null, add index i9(key9);
 | |
| alter table t3 add keyA int not null, add index iA(keyA);
 | |
| alter table t3 add keyB int not null, add index iB(keyB);
 | |
| alter table t3 add keyC int not null, add index iC(keyC);
 | |
| update t3 set key9=key1,keyA=key1,keyB=key1,keyC=key1;
 | |
| explain select * from t3 where 
 | |
| key1=1 or key2=2 or key3=3 or key4=4 or
 | |
| key5=5 or key6=6 or key7=7 or key8=8 or
 | |
| key9=9 or keyA=10 or keyB=11 or keyC=12;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t3	index_merge	i1,i2,i3,i4,i5,i6,i7,i8,i9,iA,iB,iC	i1,i2,i3,i4,i5,i6,i7,i8,i9,iA,iB,iC	4,4,4,4,4,4,4,4,4,4,4,4	NULL	12	Using union(i1,i2,i3,i4,i5,i6,i7,i8,i9,iA,iB,iC); Using where
 | |
| select * from t3 where
 | |
| key1=1 or key2=2 or key3=3 or key4=4 or
 | |
| key5=5 or key6=6 or key7=7 or key8=8 or
 | |
| key9=9 or keyA=10 or keyB=11 or keyC=12;
 | |
| key1	key2	key3	key4	key5	key6	key7	key8	key9	keyA	keyB	keyC
 | |
| 1	1	1	1	1	1	1	1023	1	1	1	1
 | |
| 2	2	2	2	2	2	2	1022	2	2	2	2
 | |
| 3	3	3	3	3	3	3	1021	3	3	3	3
 | |
| 4	4	4	4	4	4	4	1020	4	4	4	4
 | |
| 5	5	5	5	5	5	5	1019	5	5	5	5
 | |
| 6	6	6	6	6	6	6	1018	6	6	6	6
 | |
| 7	7	7	7	7	7	7	1017	7	7	7	7
 | |
| 9	9	9	9	9	9	9	1015	9	9	9	9
 | |
| 10	10	10	10	10	10	10	1014	10	10	10	10
 | |
| 11	11	11	11	11	11	11	1013	11	11	11	11
 | |
| 12	12	12	12	12	12	12	1012	12	12	12	12
 | |
| 1016	1016	1016	1016	1016	1016	1016	8	1016	1016	1016	1016
 | |
| explain select * from t0 where key1 < 3 or key2 < 4;
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	t0	index_merge	i1,i2	i1,i2	4,4	NULL	7	Using sort_union(i1,i2); Using where
 | |
| select * from t0 where key1 < 3 or key2 < 4;
 | |
| key1	key2	key3	key4	key5	key6	key7	key8
 | |
| 1	1	1	1	1	1	1	1023
 | |
| 2	2	2	2	2	2	2	1022
 | |
| 3	3	3	3	3	3	3	1021
 | |
| update t0 set key8=123 where key1 < 3 or key2 < 4;
 | |
| select * from t0 where key1 < 3 or key2 < 4;
 | |
| key1	key2	key3	key4	key5	key6	key7	key8
 | |
| 1	1	1	1	1	1	1	123
 | |
| 2	2	2	2	2	2	2	123
 | |
| 3	3	3	3	3	3	3	123
 | |
| delete from t0 where key1 < 3 or key2 < 4;
 | |
| select * from t0 where key1 < 3 or key2 < 4;
 | |
| key1	key2	key3	key4	key5	key6	key7	key8
 | |
| select count(*) from t0;
 | |
| count(*)
 | |
| 1021
 | |
| drop table t4;
 | |
| create table t4 (a int);
 | |
| insert into t4 values (1),(4),(3);
 | |
| set @save_join_buffer_size=@@join_buffer_size;
 | |
| set join_buffer_size= 4000;
 | |
| explain select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) 
 | |
| from t0 as A force index(i1,i2), t0 as B force index (i1,i2) 
 | |
| where (A.key1 < 500000 or A.key2 < 3)
 | |
| and   (B.key1 < 500000 or B.key2 < 3);
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	A	index_merge	i1,i2	i1,i2	4,4	NULL	1013	Using sort_union(i1,i2); Using where
 | |
| 1	SIMPLE	B	index_merge	i1,i2	i1,i2	4,4	NULL	1013	Using sort_union(i1,i2); Using where
 | |
| select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) 
 | |
| from t0 as A force index(i1,i2), t0 as B force index (i1,i2) 
 | |
| where (A.key1 < 500000 or A.key2 < 3)
 | |
| and   (B.key1 < 500000 or B.key2 < 3);
 | |
| max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5)
 | |
| 10240
 | |
| update t0 set key1=1;
 | |
| explain select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) 
 | |
| from t0 as A force index(i1,i2), t0 as B force index (i1,i2) 
 | |
| where (A.key1 = 1 or A.key2 = 1)
 | |
| and   (B.key1 = 1 or B.key2 = 1);
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	A	index_merge	i1,i2	i1,i2	4,4	NULL	1020	Using union(i1,i2); Using where
 | |
| 1	SIMPLE	B	index_merge	i1,i2	i1,i2	4,4	NULL	1020	Using union(i1,i2); Using where
 | |
| select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) 
 | |
| from t0 as A force index(i1,i2), t0 as B force index (i1,i2) 
 | |
| where (A.key1 = 1 or A.key2 = 1)
 | |
| and   (B.key1 = 1 or B.key2 = 1);
 | |
| max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5)
 | |
| 8194
 | |
| alter table t0 add filler1 char(200), add filler2 char(200), add filler3 char(200);
 | |
| update t0 set key2=1, key3=1, key4=1, key5=1,key6=1,key7=1 where key7 < 500;
 | |
| explain select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) 
 | |
| from t0 as A, t0 as B 
 | |
| where (A.key1 = 1 and A.key2 = 1 and A.key3 = 1 and A.key4=1 and A.key5=1 and A.key6=1 and A.key7 = 1 or A.key8=1)
 | |
| and (B.key1 = 1 and B.key2 = 1 and B.key3 = 1 and B.key4=1 and B.key5=1 and B.key6=1 and B.key7 = 1 or B.key8=1);
 | |
| id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 | |
| 1	SIMPLE	A	index_merge	i1,i2,i3,i4,i5,i6,i7?,i8	i2,i3,i4,i5,i6,i7?,i8	X	NULL	#	Using union(intersect(i2,i3,i4,i5,i6,i7?),i8); Using where
 | |
| 1	SIMPLE	B	index_merge	i1,i2,i3,i4,i5,i6,i7?,i8	i2,i3,i4,i5,i6,i7?,i8	X	NULL	#	Using union(intersect(i2,i3,i4,i5,i6,i7?),i8); Using where
 | |
| select max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5) 
 | |
| from t0 as A, t0 as B 
 | |
| where (A.key1 = 1 and A.key2 = 1 and A.key3 = 1 and A.key4=1 and A.key5=1 and A.key6=1 and A.key7 = 1 or A.key8=1)
 | |
| and (B.key1 = 1 and B.key2 = 1 and B.key3 = 1 and B.key4=1 and B.key5=1 and B.key6=1 and B.key7 = 1 or B.key8=1);
 | |
| max(A.key1 + B.key1 + A.key2 + B.key2 + A.key3 + B.key3 + A.key4 + B.key4 + A.key5 + B.key5)
 | |
| 8186
 | |
| set join_buffer_size= @save_join_buffer_size;
 | |
| drop table t0, t1, t2, t3, t4;
 | 
