2011-12-13 15:33:52.978087+00:00 https://api.launchpad.net/1.0/bugs/694443 https://api.launchpad.net/1.0/~philip-stoev https://api.launchpad.net/1.0/maria/+milestone/5.3 https://api.launchpad.net/1.0/bugs/694443/linked_branches https://api.launchpad.net/1.0/bugs/694443/activity https://bugs.launchpad.net/bugs/694443 Philip Stoev Igor Babaev Maria 5.3 Fix Released Critical 2010-12-26 10:03:00.901623+00:00 bug Philip Stoev added bug maria: assignee Philip Stoev maria: milestone Philip Stoev description Philip Stoev maria: status Igor Babaev maria: importance Igor Babaev maria: status Igor Babaev maria: status Igor Babaev maria: status Daniel Bartholomew Philip Stoev Philip Stoev Igor Babaev CREATE TABLE t1 (a int PRIMARY KEY); Query OK, 0 rows affected (0.02 sec) MariaDB [test]> INSERT INTO t1 VALUES -> (7), (4), (9), (1), (3), (8), (2); Query OK, 7 rows affected (0.01 sec) Records: 7 Duplicates: 0 Warnings: 0 MariaDB [test]> CREATE TABLE t2 (a int, b int, INDEX idx (a)); Query OK, 0 rows affected (0.00 sec) MariaDB [test]> INSERT INTO t2 VALUES -> (NULL,10), (4,80), (7,70), (6,11), (7,90), (NULL,40), -> (4,77), (4,50), (NULL,41), (7,99), (7,88), (8,12), -> (1,21), (4,90), (7,91), (8,22), (6,92), (NULL,42), -> (2,78), (2,51), (1,43), (5,97), (5,89); Query OK, 23 rows affected (0.00 sec) Records: 23 Duplicates: 0 Warnings: 0 MariaDB [test]> MariaDB [test]> SET SESSION join_cache_level = 1; Query OK, 0 rows affected (0.00 sec) MariaDB [test]> EXPLAIN -> SELECT * FROM t1,t2 WHERE t1.a < 3 and t2.a IS NULL; +----+-------------+-------+-------+---------------+---------+---------+-------+------+--------------------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+-------+---------------+---------+---------+-------+------+--------------------------+ | 1 | SIMPLE | t1 | range | PRIMARY | PRIMARY | 4 | NULL | 3 | Using where; Using index | | 1 | SIMPLE | t2 | ref | idx | idx | 5 | const | 4 | Using index condition | +----+-------------+-------+-------+---------------+---------+---------+-------+------+--------------------------+ 2 rows in set (0.00 sec) MariaDB [test]> SELECT * FROM t1,t2 WHERE t1.a < 3 and t2.a IS NULL; +---+------+------+ | a | a | b | +---+------+------+ | 1 | NULL | 10 | | 1 | NULL | 40 | | 1 | NULL | 41 | | 1 | NULL | 42 | | 2 | NULL | 10 | | 2 | NULL | 40 | | 2 | NULL | 41 | | 2 | NULL | 42 | +---+------+------+ 8 rows in set (0.00 sec) MariaDB [test]> SET SESSION join_cache_level = 4; Query OK, 0 rows affected (0.00 sec) MariaDB [test]> EXPLAIN -> SELECT * FROM t1,t2 WHERE t1.a < 3 and t2.a IS NULL; +----+-------------+-------+-------+---------------+---------+---------+-------+------+--------------------------------------------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+-------+---------------+---------+---------+-------+------+--------------------------------------------------+ | 1 | SIMPLE | t1 | range | PRIMARY | PRIMARY | 4 | NULL | 3 | Using where; Using index | | 1 | SIMPLE | t2 | ref | idx | idx | 5 | const | 4 | Using where; Using join buffer (flat, BNLH join) | +----+-------------+-------+-------+---------------+---------+---------+-------+------+--------------------------------------------------+ 2 rows in set (0.00 sec) MariaDB [test]> SELECT * FROM t1,t2 WHERE t1.a < 3 and t2.a IS NULL; Empty set (0.00 sec) ]]>