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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
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@ -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;