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| author | Sergei Golubchik <sergii@pisem.net> | 2014-03-20 23:27:08 +0100 |
|---|---|---|
| committer | Sergei Golubchik <sergii@pisem.net> | 2014-03-20 23:27:08 +0100 |
| commit | 3bb249612fe3864f152aa990d4d5f267ac9bb688 (patch) | |
| tree | 4d3c2f0d1b2d4334ed098bf4d7955570045d065e /mysql-test/r/key.result | |
| parent | dee0fd42334f9ec03dd761d9fabbdecedcb31528 (diff) | |
| download | mariadb-git-3bb249612fe3864f152aa990d4d5f267ac9bb688.tar.gz | |
MDEV-5846 MySQL Bug #18144 - Cost with FORCE/USE index seems incorrect in some cases.
Diffstat (limited to 'mysql-test/r/key.result')
| -rw-r--r-- | mysql-test/r/key.result | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/mysql-test/r/key.result b/mysql-test/r/key.result index 2479308a2c4..a89a79dadbb 100644 --- a/mysql-test/r/key.result +++ b/mysql-test/r/key.result @@ -612,3 +612,30 @@ SELECT 1 as RES FROM t1 AS t1_outer WHERE (SELECT max(b) FROM t1 GROUP BY a HAVING a < 2) > 12; RES DROP TABLE t1; +# +# Bug#18144: Cost with FORCE/USE index seems incorrect in some cases. +# +# We are interested in showing that the cost for the last plan is higher +# than for the preceding two plans. +# +CREATE TABLE t1( a INT, b INT, KEY( a ) ); +INSERT INTO t1 values (1, 2), (1, 3), (2, 3), (2, 4), (3, 4), (3, 5); +EXPLAIN SELECT a, SUM( b ) FROM t1 GROUP BY a; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 ALL NULL NULL NULL NULL 6 Using temporary; Using filesort +SHOW STATUS LIKE 'Last_query_cost'; +Variable_name Value +Last_query_cost 9.212184 +EXPLAIN SELECT a, SUM( b ) FROM t1 USE INDEX( a ) GROUP BY a; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 ALL NULL NULL NULL NULL 6 Using temporary; Using filesort +SHOW STATUS LIKE 'Last_query_cost'; +Variable_name Value +Last_query_cost 9.212184 +EXPLAIN SELECT a, SUM( b ) FROM t1 FORCE INDEX( a ) GROUP BY a; +id select_type table type possible_keys key key_len ref rows Extra +1 SIMPLE t1 index NULL a 5 NULL 6 +SHOW STATUS LIKE 'Last_query_cost'; +Variable_name Value +Last_query_cost 14.199000 +DROP TABLE t1; |