| Bug #3115 | CAST AS DATE with malformed string returns NULL but IS NULL is false. | ||
|---|---|---|---|
| Submitted: | 9 Mar 2004 7:50 | Modified: | 9 Mar 2004 13:19 |
| Reporter: | Per-Erik Martin | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | MySQL Server | Severity: | S2 (Serious) |
| Version: | 4.1 | OS: | Any (Any) |
| Assigned to: | Jani Tolonen | CPU Architecture: | Any |
[9 Mar 2004 8:31]
Dean Ellis
Verified against 4.1.2.
SELECT CAST('20030x12' AS DATE) <=> NULL; reports true.
[9 Mar 2004 13:19]
Jani Tolonen
Thank you for your bug report. This issue has been committed to our
source repository of that product and will be incorporated into the
next release.
If necessary, you can access the source repository and build the latest
available version, including the bugfix, yourself. More information
about accessing the source trees is available at
http://www.mysql.com/doc/en/Installing_source_tree.html
Additional info:
Fix will be in 4.1.2.
bk ChangeSet 1.1773
Description: CAST('20030x12' AS DATE) returns NULL when used in a SELECT or set to a user defined variable, but testing with IS NULL returns false (0). (Note: Maybe the SQL-99/2003-ish way would be to return an error?) How to repeat: mysql> select cast('20030312' as date); +--------------------------+ | cast('20030312' as date) | +--------------------------+ | 2003-03-12 | +--------------------------+ 1 row in set (0.00 sec) mysql> select cast('20030x12' as date); +--------------------------+ | cast('20030x12' as date) | +--------------------------+ | NULL | +--------------------------+ 1 row in set (0.00 sec) mysql> select cast('20030x12' as date) is null; +----------------------------------+ | cast('20030x12' as date) is null | +----------------------------------+ | 0 | +----------------------------------+ 1 row in set (0.00 sec) mysql> set @x = cast('20030x12' as date); Query OK, 0 rows affected (0.00 sec) mysql> select @x, @x is null; +------+------------+ | @x | @x is null | +------+------------+ | NULL | 1 | +------+------------+ 1 row in set (0.00 sec)