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			122 lines
		
	
	
	
		
			5.6 KiB
		
	
	
	
		
			Text
		
	
	
	
	
	
			
		
		
	
	
			122 lines
		
	
	
	
		
			5.6 KiB
		
	
	
	
		
			Text
		
	
	
	
	
	
drop table if exists t0, t1, t2, t3, t4;
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set @save_optimizer_switch=@@optimizer_switch;
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set optimizer_switch='semijoin=on,materialization=on';
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set optimizer_switch='mrr=on,mrr_sort_keys=on,index_condition_pushdown=on';
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create table t0 (a int);
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insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
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create table t1 as select * from t0;
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# The following should use full scan on <subquery2> and it must scan 1 row:
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explain select * from t0 where a in (select max(a) from t1);
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id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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1	PRIMARY	<subquery2>	ALL	distinct_key	NULL	NULL	NULL	1	
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1	PRIMARY	t0	ALL	NULL	NULL	NULL	NULL	10	Using where; Using join buffer (flat, BNL join)
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2	MATERIALIZED	t1	ALL	NULL	NULL	NULL	NULL	10	
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select * from t0 where a in (select max(a) from t1);
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a
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9
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insert into t1 values (11);
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select * from t0 where a in (select max(a) from t1);
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a
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delete from t1 where a=11;
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insert into t0 values (NULL);
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select * from t0 where a in (select max(a) from t1);
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a
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9
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delete from t0 where a is NULL;
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delete from t1;
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select * from t0 where a in (select max(a) from t1);
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a
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insert into t0 values (NULL);
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select * from t0 where a in (select max(a) from t1);
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a
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delete from t0 where a is NULL;
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drop table t1;
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create table t1 (a int, b int);
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insert into t1 select a,a from t0;
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create table t2 as select * from t1 where a<5;
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create table t3 as select (A.a + 10*B.a) as a from t0 A, t0 B;
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alter table t3 add primary key(a);
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# The following should have do a full scan on <subquery2> and scan 5 rows 
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#   (despite that subquery's join output estimate is 50 rows)
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explain select * from t3 where a in (select max(t2.a) from t1, t2 group by t2.b);
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id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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1	PRIMARY	<subquery2>	ALL	distinct_key	NULL	NULL	NULL	5	
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1	PRIMARY	t3	eq_ref	PRIMARY	PRIMARY	8	<subquery2>.max(t2.a)	1	Using where; Using index
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2	MATERIALIZED	t2	ALL	NULL	NULL	NULL	NULL	5	Using temporary
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2	MATERIALIZED	t1	ALL	NULL	NULL	NULL	NULL	10	Using join buffer (flat, BNL join)
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# Compare to this which really will have 50 record combinations:
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explain select * from t3 where a in (select max(t2.a) from t1, t2 group by t2.b, t1.b);
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id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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1	PRIMARY	t3	index	PRIMARY	PRIMARY	8	NULL	100	Using index
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1	PRIMARY	<subquery2>	eq_ref	distinct_key	distinct_key	4	test.t3.a	1	Using where
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2	MATERIALIZED	t2	ALL	NULL	NULL	NULL	NULL	5	Using temporary
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2	MATERIALIZED	t1	ALL	NULL	NULL	NULL	NULL	10	Using join buffer (flat, BNL join)
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SET @save_optimizer_switch=@@optimizer_switch;
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SET optimizer_switch='outer_join_with_cache=off';
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# Outer joins also work:
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explain select * from t3 
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where a in (select max(t2.a) from t1 left join t2 on t1.a=t2.a group by t2.b, t1.b);
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id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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1	PRIMARY	t3	index	PRIMARY	PRIMARY	8	NULL	100	Using index
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1	PRIMARY	<subquery2>	eq_ref	distinct_key	distinct_key	4	test.t3.a	1	Using where
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2	MATERIALIZED	t1	ALL	NULL	NULL	NULL	NULL	10	Using temporary
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2	MATERIALIZED	t2	ALL	NULL	NULL	NULL	NULL	5	Using where
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SET optimizer_switch=@save_optimizer_switch;
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create table t4 (a int, b int, filler char(20), unique key(a,b));
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insert into t4 select A.a + 10*B.a, A.a + 10*B.a, 'filler' from t0 A, t0 B;
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explain select * from t0, t4 where 
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t4.b=t0.a and t4.a in (select max(t2.a) from t1, t2 group by t2.b);
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id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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1	PRIMARY	<subquery2>	ALL	distinct_key	NULL	NULL	NULL	5	
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1	PRIMARY	t0	ALL	NULL	NULL	NULL	NULL	10	Using where; Using join buffer (flat, BNL join)
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1	PRIMARY	t4	eq_ref	a	a	10	<subquery2>.max(t2.a),test.t0.a	1	
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2	MATERIALIZED	t2	ALL	NULL	NULL	NULL	NULL	5	Using temporary
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2	MATERIALIZED	t1	ALL	NULL	NULL	NULL	NULL	10	Using join buffer (flat, BNL join)
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insert into t4 select 100 + (B.a *100 + A.a), 100 + (B.a*100 + A.a), 'filler' from t4 A, t0 B;
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explain select * from t4 where 
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t4.a in (select max(t2.a) from t1, t2 group by t2.b) and 
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t4.b in (select max(t2.a) from t1, t2 group by t2.b);
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id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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1	PRIMARY	<subquery3>	ALL	distinct_key	NULL	NULL	NULL	5	
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1	PRIMARY	<subquery2>	ALL	distinct_key	NULL	NULL	NULL	5	Using join buffer (flat, BNL join)
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1	PRIMARY	t4	eq_ref	a	a	10	<subquery2>.max(t2.a),<subquery3>.max(t2.a)	1	
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3	MATERIALIZED	t2	ALL	NULL	NULL	NULL	NULL	5	Using temporary
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3	MATERIALIZED	t1	ALL	NULL	NULL	NULL	NULL	10	Using join buffer (flat, BNL join)
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2	MATERIALIZED	t2	ALL	NULL	NULL	NULL	NULL	5	Using temporary
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2	MATERIALIZED	t1	ALL	NULL	NULL	NULL	NULL	10	Using join buffer (flat, BNL join)
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drop table t1,t2,t3,t4;
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drop table t0;
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#
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# BUG#780359: Crash with get_fanout_with_deps in maria-5.3-mwl90
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#
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CREATE TABLE t1 (f1 int);
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INSERT INTO t1 VALUES (2),(2);
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CREATE TABLE t2 (f3 int);
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INSERT INTO t2 VALUES (2),(2);
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SELECT *
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FROM t1
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WHERE ( f1 ) IN (
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SELECT t2.f3
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FROM t2
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WHERE t2.f3 = 97
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AND t2.f3 = 50
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GROUP BY 1
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);
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f1
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DROP TABLE t1, t2;
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#
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# BUG#727183: WL#90 does not trigger with non-comma joins
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#
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create table t0 (a int);
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insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
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create table t1(a int, key(a));
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insert into t1 select A.a + 10*B.a + 100*C.a from t0 A, t0 B, t0 C;
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# The following must use non-merged SJ-Materialization:
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explain select * from t1 X join t0 Y on X.a < Y.a where X.a in (select max(a) from t0);
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id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
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1	PRIMARY	<subquery2>	ALL	distinct_key	NULL	NULL	NULL	1	
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1	PRIMARY	X	ref	a	a	5	<subquery2>.max(a)	1	Using index
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1	PRIMARY	Y	ALL	NULL	NULL	NULL	NULL	10	Using where; Using join buffer (flat, BNL join)
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2	MATERIALIZED	t0	ALL	NULL	NULL	NULL	NULL	10	
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drop table t0, t1;
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set optimizer_switch=@save_optimizer_switch;
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