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Bug #21180: Subselect with index for both WHERE and ORDER BY produces empty result

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Reseting subqueries with "quick" access methods was incomplete.
 Partially backported the correct reseting of QUICK_SELECTs from 5.x.
This commit is contained in:
gkodinov/kgeorge@macbook.gmz
2006-08-03 19:20:30 +03:00
parent 40a1fbdffb
commit 3183f73601
4 changed files with 70 additions and 3 deletions
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29
mysql-test/r/subselect.result
View File

@ -2895,3 +2895,32 @@ select * from t1 where NOT(s1 = ALL (select s1/s1 from t1));
s1
2
drop table t1;
create table t1(a int, primary key (a));
insert into t1 values (10);
create table t2 (a int primary key, b varchar(32), c int, unique key b(c, b));
insert into t2(a, c, b) values (1,10,'359'), (2,10,'35988'), (3,10,'35989');
explain SELECT sql_no_cache t1.a, r.a, r.b FROM t1 LEFT JOIN t2 r
ON r.a = (SELECT t2.a FROM t2 WHERE t2.c = t1.a AND t2.b <= '359899'
ORDER BY t2.c DESC, t2.b DESC LIMIT 1) WHERE t1.a = 10;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 system PRIMARY NULL NULL NULL 1
1 PRIMARY r const PRIMARY PRIMARY 4 const 1
2 DEPENDENT SUBQUERY t2 range b b 38 NULL 2 Using where
SELECT sql_no_cache t1.a, r.a, r.b FROM t1 LEFT JOIN t2 r
ON r.a = (SELECT t2.a FROM t2 WHERE t2.c = t1.a AND t2.b <= '359899'
ORDER BY t2.c DESC, t2.b DESC LIMIT 1) WHERE t1.a = 10;
a a b
10 3 35989
explain SELECT sql_no_cache t1.a, r.a, r.b FROM t1 LEFT JOIN t2 r
ON r.a = (SELECT t2.a FROM t2 WHERE t2.c = t1.a AND t2.b <= '359899'
ORDER BY t2.c, t2.b LIMIT 1) WHERE t1.a = 10;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 system PRIMARY NULL NULL NULL 1
1 PRIMARY r const PRIMARY PRIMARY 4 const 1
2 DEPENDENT SUBQUERY t2 range b b 38 NULL 2 Using where
SELECT sql_no_cache t1.a, r.a, r.b FROM t1 LEFT JOIN t2 r
ON r.a = (SELECT t2.a FROM t2 WHERE t2.c = t1.a AND t2.b <= '359899'
ORDER BY t2.c, t2.b LIMIT 1) WHERE t1.a = 10;
a a b
10 1 359
drop table t1,t2;

26
mysql-test/t/subselect.test
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@ -1861,4 +1861,30 @@ select * from t1 where NOT(s1+1 = ANY (select s1 from t1));
select * from t1 where (s1 = ALL (select s1/s1 from t1));
select * from t1 where NOT(s1 = ALL (select s1/s1 from t1));
drop table t1;
#
# Bug #21180: Subselect with index for both WHERE and ORDER BY
# produces empty result
#
create table t1(a int, primary key (a));
insert into t1 values (10);
create table t2 (a int primary key, b varchar(32), c int, unique key b(c, b));
insert into t2(a, c, b) values (1,10,'359'), (2,10,'35988'), (3,10,'35989');
explain SELECT sql_no_cache t1.a, r.a, r.b FROM t1 LEFT JOIN t2 r
ON r.a = (SELECT t2.a FROM t2 WHERE t2.c = t1.a AND t2.b <= '359899'
ORDER BY t2.c DESC, t2.b DESC LIMIT 1) WHERE t1.a = 10;
SELECT sql_no_cache t1.a, r.a, r.b FROM t1 LEFT JOIN t2 r
ON r.a = (SELECT t2.a FROM t2 WHERE t2.c = t1.a AND t2.b <= '359899'
ORDER BY t2.c DESC, t2.b DESC LIMIT 1) WHERE t1.a = 10;
explain SELECT sql_no_cache t1.a, r.a, r.b FROM t1 LEFT JOIN t2 r
ON r.a = (SELECT t2.a FROM t2 WHERE t2.c = t1.a AND t2.b <= '359899'
ORDER BY t2.c, t2.b LIMIT 1) WHERE t1.a = 10;
SELECT sql_no_cache t1.a, r.a, r.b FROM t1 LEFT JOIN t2 r
ON r.a = (SELECT t2.a FROM t2 WHERE t2.c = t1.a AND t2.b <= '359899'
ORDER BY t2.c, t2.b LIMIT 1) WHERE t1.a = 10;
drop table t1,t2;
# End of 4.1 tests

14
sql/opt_range.cc
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@ -2980,6 +2980,14 @@ int QUICK_SELECT::get_next()
}
}
void QUICK_SELECT::reset(void)
{
next= 0;
it.rewind();
range= 0;
if (file->inited == handler::NONE)
file->ha_index_init(index);
}
/* Get next for geometrical indexes */
@ -3201,7 +3209,11 @@ bool QUICK_SELECT_DESC::test_if_null_range(QUICK_RANGE *range_arg,
return 0;
}
#endif
void QUICK_SELECT_DESC::reset(void)
{
rev_it.rewind();
QUICK_SELECT::reset();
}
/*****************************************************************************
** Print a quick range for debugging

4
sql/opt_range.h
View File

@ -86,7 +86,7 @@ public:
QUICK_SELECT(THD *thd, TABLE *table,uint index_arg,bool no_alloc=0);
virtual ~QUICK_SELECT();
void reset(void) { next=0; it.rewind(); }
virtual void reset(void);
int init()
{
key_part_info= head->key_info[index].key_part;
@ -120,7 +120,7 @@ private:
#ifdef NOT_USED
bool test_if_null_range(QUICK_RANGE *range, uint used_key_parts);
#endif
void reset(void) { next=0; rev_it.rewind(); }
void reset(void);
List<QUICK_RANGE> rev_ranges;
List_iterator<QUICK_RANGE> rev_it;
};