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To correctly decide which predicates can be evaluated with a given table the optimizer must know the exact set of tables that a predicate depends on. If that mask is too wide (refer to non-existing tables) the optimizer can erroneously skip a predicate. One such case of wrong table usage mask were the aggregate functions. The have a all-1 mask (meaning depend on all tables, including non-existent ones). Fixed by making a real used_tables mask for the aggregates. The mask is constructed in the following way : 1. OR the table dependency masks of all the arguments of the aggregate. 2. If all the arguments of the function are from the local name resolution context and it is evaluated in the same name resolution context where it is referenced all the tables from that name resolution context are OR-ed to the dependency mask. This is to denote that an aggregate function depends on the number of rows it processes. 3. Handle correctly the case of an aggregate function optimization (such that the aggregate function can be pre-calculated and made a constant). Made sure that an aggregate function is never a constant (unless subject of a specific optimization and pre-calculation). One other flaw was revealed and fixed in the process : references were not calling the recalculation method for used_tables of their targets. mysql-test/r/subselect3.result: Bug #24484: test case mysql-test/t/subselect3.test: Bug #24484: test case sql/item.h: Bug #24484: Item_ref must update the used tables. sql/item_sum.cc: Bug #24484: correct calculation of used_tables for aggregates. sql/item_sum.h: Bug #24484: correct calculation of used_tables for aggregates. sql/opt_range.cc: Bug #24484: fixed ref resolution in loose index scan sql/sql_base.cc: Bug #24484: moved counting of leaf tables inside setup_tables_and_check_access. sql/sql_class.h: Bug #24484: changed table count to more narrow type. sql/sql_insert.cc: Bug #24484: moved counting of leaf tables inside setup_tables_and_check_access. Substract the first table (and its subtables) of an INSERT statement from leaf_count. sql/sql_select.cc: Bug #24484: correct check for aggregates
532 lines
15 KiB
Text
532 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, AVG(b), (SELECT t.c FROM t1 AS t WHERE t1.a=t.a AND t.b=AVG(t1.b))
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AS test FROM t1 GROUP BY a;
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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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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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