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The Item_outer_ref class based on the Item_direct_ref class was always used to represent an outer field. But if the outer select is a grouping one and the outer field isn't under an aggregate function which is aggregated in that outer select an Item_ref object should be used to represent such a field. If the outer select in which the outer field is resolved isn't grouping then the Item_field class should be used to represent such a field. This logic also should be used for an outer field resolved through its alias name. Now the Item_field::fix_outer_field() uses Item_outer_field objects to represent aliased and non-aliased outer fields for grouping outer selects only. Now the fix_inner_refs() function chooses which class to use to access outer field - the Item_ref or the Item_direct_ref. An object of the chosen class substitutes the original field in the Item_outer_ref object. The direct_ref and the found_in_select_list fields were added to the Item_outer_ref class. mysql-test/t/subselect3.test: Some test cases were corrected after the fix for the bug#27321. mysql-test/r/subselect3.result: Some test cases were corrected after the fix for the bug#27321. mysql-test/t/subselect.test: Added a test case for the bug#27321: Wrong subquery result in a grouping select. mysql-test/r/subselect.result: Added a test case for the bug#27321: Wrong subquery result in a grouping select. Some test cases were corrected after this fix. sql/sql_union.cc: Bug#27321: Wrong subquery result in a grouping select. Cleanup of the inner_refs_list. sql/sql_select.cc: Bug#27321: Wrong subquery result in a grouping select. Now the fix_inner_refs() function chooses which class to use to access outer field - the Item_ref or the Item_direct_ref. An object of the chosen class substitutes the original field in the Item_outer_ref object. A comment is corrected. sql/item.cc: Bug#27321: Wrong subquery result in a grouping select. Now the Item_field::fix_outer_field() uses Item_outer_field objects to represent aliased and non-aliased outer fields for grouping outer selects only. sql/item.h: Bug#27321: Wrong subquery result in a grouping select. The direct_ref and the found_in_select_list fields were added to the Item_outer_ref class.
530 lines
15 KiB
Text
530 lines
15 KiB
Text
--disable_warnings
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drop table if exists t0, t1, t2, t3, t4;
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--enable_warnings
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#
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# 1. Subquery with GROUP/HAVING
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#
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create table t1 (oref int, grp int, ie int) ;
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insert into t1 (oref, grp, ie) values
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(1, 1, 1),
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(1, 1, 1),
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(1, 2, NULL),
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(2, 1, 3),
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(3, 1, 4),
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(3, 2, NULL);
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# Ok, for
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# select max(ie) from t1 where oref=PARAM group by grp
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# we'll have:
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# PARAM subquery result
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# 1 -> {(1), (NULL)} matching + NULL
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# 2 -> {(3)} non-matching
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# 3 -> {(3), (NULL)} non-matching + NULL
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# 4 -> {} empty set
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create table t2 (oref int, a int);
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insert into t2 values
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(1, 1),
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(2, 2),
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(3, 3),
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(4, NULL),
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(2, NULL);
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# true, false, null, false, null
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select a, oref, a in (select max(ie)
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from t1 where oref=t2.oref group by grp) Z from t2;
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# This must have a trigcond
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explain extended
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select a, oref, a in (select max(ie)
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from t1 where oref=t2.oref group by grp) Z from t2;
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# This must not have a trigcond:
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explain extended
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select a, oref from t2
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where a in (select max(ie) from t1 where oref=t2.oref group by grp);
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select a, oref, a in (
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select max(ie) from t1 where oref=t2.oref group by grp union
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select max(ie) from t1 where oref=t2.oref group by grp
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) Z from t2;
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# Non-correlated subquery, 2 NULL evaluations
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create table t3 (a int);
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insert into t3 values (NULL), (NULL);
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flush status;
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select a in (select max(ie) from t1 where oref=4 group by grp) from t3;
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show status like 'Handler_read_rnd_next';
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select ' ^ This must show 11' Z;
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# This must show trigcond:
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explain extended select a in (select max(ie) from t1 where oref=4 group by grp) from t3;
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drop table t1, t2, t3;
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#
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# 2. Subquery handled with 'index_subquery':
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#
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create table t1 (a int, oref int, key(a));
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insert into t1 values
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(1, 1),
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(1, NULL),
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(2, 3),
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(2, NULL),
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(3, NULL);
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create table t2 (a int, oref int);
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insert into t2 values (1, 1), (2,2), (NULL, 3), (NULL, 4);
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select oref, a, a in (select a from t1 where oref=t2.oref) Z from t2;
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# The next explain shows "using index" but that is just incorrect display
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# (there is a bug filed about this).
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explain extended
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select oref, a, a in (select a from t1 where oref=t2.oref) Z from t2;
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flush status;
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select oref, a from t2 where a in (select a from t1 where oref=t2.oref);
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# This will only show access to t2:
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show status like '%Handler_read_rnd_next';
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# Check that repeated NULL-scans are not cached (subq. is not correlated):
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delete from t2;
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insert into t2 values (NULL, 0),(NULL, 0), (NULL, 0), (NULL, 0);
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flush status;
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select oref, a, a in (select a from t1 where oref=t2.oref) Z from t2;
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show status like '%Handler_read%';
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select 'No key lookups, seq reads: 29= 5 reads from t2 + 4 * 6 reads from t1.' Z;
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drop table t1, t2;
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#
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# 3. Subquery handled with 'unique_index_subquery':
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#
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create table t1 (a int, b int, primary key (a));
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insert into t1 values (1,1), (3,1),(100,1);
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create table t2 (a int, b int);
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insert into t2 values (1,1),(2,1),(NULL,1),(NULL,0);
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select a,b, a in (select a from t1 where t1.b = t2.b) Z from t2 ;
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drop table t1, t2;
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#
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# 4. Subquery that is a join, with ref access
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#
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create table t1 (a int, b int, key(a));
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insert into t1 values
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(0,0),(1,1),(2,2),(3,3),(4,4),(5,5),(6,6),(7,7),(8,8),(9,9);
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create table t2 like t1;
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insert into t2 select * from t1;
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update t2 set b=1;
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create table t3 (a int, oref int);
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insert into t3 values (1, 1), (NULL,1), (NULL,0);
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select a, oref,
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t3.a in (select t1.a from t1, t2 where t1.b=t2.a and t2.b=t3.oref) Z
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from t3;
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# This must have trigcond in WHERE and HAVING:
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explain extended
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select a, oref,
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t3.a in (select t1.a from t1, t2 where t1.b=t2.a and t2.b=t3.oref) Z
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from t3;
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drop table t1, t2, t3;
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#
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# BUG#24085: Wrong query result for "NULL IN (SELECT ... UNION SELECT ...)"
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#
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# case 1: NULL IN (SELECT not_null_val FROM ...) w/o HAVING/GROUP-BY/etc
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create table t1 (a int NOT NULL, b int NOT NULL, key(a));
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insert into t1 values
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(0,0),(1,1),(2,2),(3,3),(4,4),(5,5),(6,6),(7,7),(8,8),(9,9);
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create table t2 like t1;
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insert into t2 select * from t1;
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update t2 set b=1;
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create table t3 (a int, oref int);
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insert into t3 values (1, 1), (NULL,1), (NULL,0);
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select a, oref,
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t3.a in (select t1.a from t1, t2 where t1.b=t2.a and t2.b=t3.oref) Z
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from t3;
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--echo This must show a trig_cond:
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explain extended
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select a, oref,
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t3.a in (select t1.a from t1, t2 where t1.b=t2.a and t2.b=t3.oref) Z
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from t3;
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drop table t1,t2,t3;
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# case 2: NULL IN (SELECT not_null_val FROM) where SELECT has GROUP BY
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create table t1 (oref int, grp int);
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insert into t1 (oref, grp) values
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(1, 1),
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(1, 1);
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# Ok, for
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# select count(*) from t1 group by grp having grp=PARAM
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# we'll have:
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# PARAM subuqery result
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# 1 -> {(2)}
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# 2 -> {} - empty set
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create table t2 (oref int, a int);
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insert into t2 values
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(1, NULL),
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(2, NULL);
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select a, oref,
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a in (select count(*) from t1 group by grp having grp=t2.oref) Z from t2;
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--echo This must show a trig_cond:
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explain extended
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select a, oref,
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a in (select count(*) from t1 group by grp having grp=t2.oref) Z from t2;
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drop table t1, t2;
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create table t1 (a int, b int, primary key (a));
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insert into t1 values (1,1), (3,1),(100,1);
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create table t2 (a int, b int);
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insert into t2 values (1,1),(2,1),(NULL,1),(NULL,0);
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select a,b, a in (select a from t1 where t1.b = t2.b union select a from
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t1 where t1.b = t2.b) Z from t2 ;
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select a,b, a in (select a from t1 where t1.b = t2.b) Z from t2 ;
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drop table t1, t2;
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#
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# BUG#24127: Incorrect results of row-based subqueries with NULLs on the left side.
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#
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create table t3 (a int);
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insert into t3 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
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create table t2 (a int, b int, oref int);
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insert into t2 values (NULL,1, 100), (NULL,2, 100);
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create table t1 (a int, b int, c int, key(a,b));
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insert into t1 select 2*A, 2*A, 100 from t3;
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# First test index subquery engine
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explain extended select a,b, oref, (a,b) in (select a,b from t1 where c=t2.oref) Z from t2;
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select a,b, oref, (a,b) in (select a,b from t1 where c=t2.oref) Z from t2;
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# Then check that we do turn off 'ref' scans in the subquery
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create table t4 (x int);
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insert into t4 select A.a + 10*B.a from t1 A, t1 B;
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explain extended
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select a,b, oref,
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(a,b) in (select a,b from t1,t4 where c=t2.oref) Z
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from t2;
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select a,b, oref,
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(a,b) in (select a,b from t1,t4 where c=t2.oref) Z
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from t2;
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drop table t1,t2,t3,t4;
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# More tests for tricky multi-column cases, where some of pushed-down
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# equalities are used for index lookups and some arent.
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create table t1 (oref char(4), grp int, ie1 int, ie2 int);
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insert into t1 (oref, grp, ie1, ie2) values
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('aa', 10, 2, 1),
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('aa', 10, 1, 1),
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('aa', 20, 2, 1),
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('bb', 10, 3, 1),
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('cc', 10, 4, 2),
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('cc', 20, 3, 2),
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('ee', 10, 2, 1),
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('ee', 10, 1, 2),
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('ff', 20, 2, 2),
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('ff', 20, 1, 2);
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create table t2 (oref char(4), a int, b int);
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insert into t2 values
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('ee', NULL, 1),
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('bb', 2, 1),
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('ff', 2, 2),
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('cc', 3, NULL),
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('bb', NULL, NULL),
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('aa', 1, 1),
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('dd', 1, NULL);
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alter table t1 add index idx(ie1,ie2);
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--cc 3 NULL NULL
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select oref, a, b, (a,b) in (select ie1,ie2 from t1 where oref=t2.oref) Z from t2 where a=3 and b is null ;
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insert into t2 values ('new1', 10,10);
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insert into t1 values ('new1', 1234, 10, NULL);
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-- new1, 10, 10, NULL,
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select oref, a, b, (a,b) in (select ie1,ie2 from t1 where oref=t2.oref) Z from t2 where a=10 and b=10;
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explain extended
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select oref, a, b, (a,b) in (select ie1,ie2 from t1 where oref=t2.oref) Z from t2 where a=10 and b=10;
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drop table t1, t2;
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# Now test different column types:
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create table t1 (oref char(4), grp int, ie int);
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insert into t1 (oref, grp, ie) values
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('aa', 10, 2),
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('aa', 10, 1),
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('aa', 20, NULL),
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('bb', 10, 3),
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('cc', 10, 4),
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('cc', 20, NULL),
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('ee', 10, NULL),
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('ee', 10, NULL),
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('ff', 20, 2),
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('ff', 20, 1);
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create table t2 (oref char(4), a int);
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insert into t2 values
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('ee', NULL),
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('bb', 2),
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('ff', 2),
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('cc', 3),
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('aa', 1),
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('dd', NULL),
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('bb', NULL);
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select oref, a, a in (select ie from t1 where oref=t2.oref) Z from t2;
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select oref, a from t2 where a in (select ie from t1 where oref=t2.oref);
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select oref, a from t2 where a not in (select ie from t1 where oref=t2.oref);
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select oref, a, a in (select min(ie) from t1 where oref=t2.oref group by grp) Z from t2;
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select oref, a from t2 where
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a in (select min(ie) from t1 where oref=t2.oref group by grp);
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select oref, a from t2 where
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a not in (select min(ie) from t1 where oref=t2.oref group by grp);
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#
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update t1 set ie=3 where oref='ff' and ie=1;
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select oref, a, a in (select min(ie) from t1 where oref=t2.oref group by
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grp) Z from t2;
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select oref, a from t2 where a in (select min(ie) from t1 where
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oref=t2.oref group by grp);
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select oref, a from t2 where a not in (select min(ie) from t1 where
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oref=t2.oref group by grp);
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select oref, a, a in (select min(ie) from t1 where oref=t2.oref group by
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grp having min(ie) > 1) Z from t2;
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select oref, a from t2 where a in (select min(ie) from t1 where
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oref=t2.oref group by grp having min(ie) > 1);
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select oref, a from t2 where a not in (select min(ie) from t1 where
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oref=t2.oref group by grp having min(ie) > 1);
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#
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alter table t1 add index idx(ie);
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explain select oref, a, a in (select ie from t1 where oref=t2.oref) Z from t2;
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select oref, a, a in (select ie from t1 where oref=t2.oref) Z from t2;
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select oref, a from t2 where a in (select ie from t1 where oref=t2.oref);
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select oref, a from t2 where a not in (select ie from t1 where oref=t2.oref);
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alter table t1 drop index idx;
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alter table t1 add index idx(oref,ie);
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explain select oref, a, a in (select ie from t1 where oref=t2.oref) Z from t2;
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select oref, a, a in (select ie from t1 where oref=t2.oref) Z from t2;
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select oref, a from t2 where a in (select ie from t1 where oref=t2.oref);
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select oref, a from t2 where a not in (select ie from t1 where oref=t2.oref);
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explain
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select oref, a,
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a in (select min(ie) from t1 where oref=t2.oref
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group by grp having min(ie) > 1) Z
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from t2;
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select oref, a,
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a in (select min(ie) from t1 where oref=t2.oref
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group by grp having min(ie) > 1) Z
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from t2;
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select oref, a from t2 where a in (select min(ie) from t1 where oref=t2.oref
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group by grp having min(ie) > 1);
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select oref, a from t2 where a not in (select min(ie) from t1 where oref=t2.oref
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group by grp having min(ie) > 1);
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drop table t1,t2;
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create table t1 (oref char(4), grp int, ie1 int, ie2 int);
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insert into t1 (oref, grp, ie1, ie2) values
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('aa', 10, 2, 1),
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('aa', 10, 1, 1),
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('aa', 20, 2, 1),
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('bb', 10, 3, 1),
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('cc', 10, 4, 2),
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('cc', 20, 3, 2),
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('ee', 10, 2, 1),
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('ee', 10, 1, 2),
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('ff', 20, 2, 2),
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('ff', 20, 1, 2);
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create table t2 (oref char(4), a int, b int);
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insert into t2 values
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('ee', NULL, 1),
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('bb', 2, 1),
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('ff', 2, 2),
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('cc', 3, NULL),
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('bb', NULL, NULL),
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('aa', 1, 1),
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('dd', 1, NULL);
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select oref, a, b, (a,b) in (select ie1,ie2 from t1 where oref=t2.oref) Z from t2;
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select oref, a, b from t2 where (a,b) in (select ie1,ie2 from t1 where oref=t2.oref);
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select oref, a, b from t2 where (a,b) not in (select ie1,ie2 from t1 where oref=t2.oref);
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select oref, a, b,
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(a,b) in (select min(ie1),max(ie2) from t1
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where oref=t2.oref group by grp) Z
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from t2;
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select oref, a, b from t2 where
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(a,b) in (select min(ie1), max(ie2) from t1 where oref=t2.oref group by grp);
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select oref, a, b from t2 where
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(a,b) not in (select min(ie1), max(ie2) from t1 where oref=t2.oref group by grp);
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alter table t1 add index idx(ie1,ie2);
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explain select oref, a, b, (a,b) in (select ie1,ie2 from t1 where oref=t2.oref) Z from t2;
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select oref, a, b, (a,b) in (select ie1,ie2 from t1 where oref=t2.oref) Z from t2;
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select oref, a, b from t2 where (a,b) in (select ie1,ie2 from t1 where oref=t2.oref);
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select oref, a, b from t2 where (a,b) not in (select ie1,ie2 from t1 where oref=t2.oref);
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explain extended
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select oref, a, b, (a,b) in (select ie1,ie2 from t1 where oref=t2.oref) Z from t2;
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drop table t1,t2;
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create table t1 (oref char(4), grp int, ie int primary key);
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insert into t1 (oref, grp, ie) values
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('aa', 10, 2),
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('aa', 10, 1),
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('bb', 10, 3),
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('cc', 10, 4),
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('cc', 20, 5),
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('cc', 10, 6);
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create table t2 (oref char(4), a int);
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insert into t2 values
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('ee', NULL),
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('bb', 2),
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('cc', 5),
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('cc', 2),
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('cc', NULL),
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('aa', 1),
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('bb', NULL);
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explain select oref, a, a in (select ie from t1 where oref=t2.oref) Z from t2;
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select oref, a, a in (select ie from t1 where oref=t2.oref) Z from t2;
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select oref, a from t2 where a in (select ie from t1 where oref=t2.oref);
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select oref, a from t2 where a not in (select ie from t1 where oref=t2.oref);
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explain
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select oref, a, a in (select min(ie) from t1 where oref=t2.oref group by grp) Z from t2;
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select oref, a, a in (select min(ie) from t1 where oref=t2.oref group by grp) Z from t2;
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drop table t1,t2;
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#
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# BUG#24420: row-based IN suqueries with aggregation when the left operand
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# of the subquery predicate may contain NULL values
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#
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create table t1 (a int, b int);
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insert into t1 values (0,0), (2,2), (3,3);
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create table t2 (a int, b int);
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insert into t2 values (1,1), (3,3);
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select a, b, (a,b) in (select a, min(b) from t2 group by a) Z from t1;
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insert into t2 values (NULL,4);
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select a, b, (a,b) in (select a, min(b) from t2 group by a) Z from t1;
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drop table t1,t2;
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#
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# Bug #24484: Aggregate function used in column list subquery gives erroneous
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# error
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#
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CREATE TABLE t1 (a int, b INT, c CHAR(10) NOT NULL, PRIMARY KEY (a, b));
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INSERT INTO t1 VALUES (1,1,'a'), (1,2,'b'), (1,3,'c'), (1,4,'d'), (1,5,'e'),
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(2,1,'f'), (2,2,'g'), (2,3,'h'), (3,4,'i'),(3,3,'j'), (3,2,'k'), (3,1,'l'),
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(1,9,'m');
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CREATE TABLE t2 (a int, b INT, c CHAR(10) NOT NULL, PRIMARY KEY (a, b));
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INSERT INTO t2 SELECT * FROM t1;
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# Gives error, but should work since it is (a, b) is the PK so only one
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# given match possible
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SELECT a, MAX(b), (SELECT t.c FROM t1 AS t WHERE t1.a=t.a AND t.b=MAX(t1.b))
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as test FROM t1 GROUP BY a;
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SELECT * FROM t1 GROUP by t1.a
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HAVING (MAX(t1.b) > (SELECT MAX(t2.b) FROM t2 WHERE t2.c < t1.c
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HAVING MAX(t2.b+t1.a) < 10));
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SELECT a,b,c FROM t1 WHERE b in (9,3,4) ORDER BY b,c;
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SELECT a, MAX(b),
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(SELECT COUNT(DISTINCT t.c) FROM t1 AS t WHERE t1.a=t.a AND t.b=MAX(t1.b)
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LIMIT 1)
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as cnt,
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(SELECT t.b FROM t1 AS t WHERE t1.a=t.a AND t.b=MAX(t1.b) LIMIT 1)
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as t_b,
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(SELECT t.c FROM t1 AS t WHERE t1.a=t.a AND t.b=MAX(t1.b) LIMIT 1)
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as t_b,
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(SELECT t.c FROM t1 AS t WHERE t1.a=t.a AND t.b=MAX(t1.b) ORDER BY t.c LIMIT 1)
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as t_b
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FROM t1 GROUP BY a;
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|
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SELECT a, MAX(b),
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|
(SELECT t.c FROM t1 AS t WHERE t1.a=t.a AND t.b=MAX(t1.b) LIMIT 1) as test
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|
FROM t1 GROUP BY a;
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DROP TABLE t1, t2;
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