| Bug #33663 | Character sets: weight_string function, varchar column, wrong result | ||
|---|---|---|---|
| Submitted: | 3 Jan 2008 17:37 | Modified: | 27 Mar 2008 18:56 |
| Reporter: | Peter Gulutzan | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | MySQL Server: Charsets | Severity: | S3 (Non-critical) |
| Version: | 6.0.5-alpha-debug | OS: | Linux (SUSE 10 64-bit) |
| Assigned to: | Alexander Barkov | CPU Architecture: | Any |
[3 Jan 2008 18:48]
Valeriy Kravchuk
Thank you for a bug report. Without order by the results are correct:
mysql> create table t (s1 varchar(5));
Query OK, 0 rows affected (0.84 sec)
mysql> insert into t values ('a'),(null);
Query OK, 2 rows affected (0.16 sec)
Records: 2 Duplicates: 0 Warnings: 0
mysql> select hex(weight_string(s1)) from t order by s1;
+------------------------+
| hex(weight_string(s1)) |
+------------------------+
| NULL |
| NULL |
+------------------------+
2 rows in set (0.09 sec)
mysql> select hex(weight_string(s1)) from t;
+------------------------+
| hex(weight_string(s1)) |
+------------------------+
| 0041 |
| NULL |
+------------------------+
2 rows in set (0.00 sec)
[17 Mar 2008 12:17]
Bugs System
A patch for this bug has been committed. After review, it may be pushed to the relevant source trees for release in the next version. You can access the patch from: http://lists.mysql.com/commits/44105 ChangeSet@1.2597, 2008-03-17 16:12:11+04:00, bar@mysql.com +3 -0 Bug#33663 Character sets: weight_string function, varchar column, wrong result Problem: null_value was checked before calling val_str(), so null_value corresponded NULL flag for the previous row. Fix: check null_value after calling val_str().
[18 Mar 2008 12:45]
Bugs System
A patch for this bug has been committed. After review, it may be pushed to the relevant source trees for release in the next version. You can access the patch from: http://lists.mysql.com/commits/44173 ChangeSet@1.2597, 2008-03-18 16:40:33+04:00, bar@mysql.com +3 -0 Bug#33663 Character sets: weight_string function, varchar column, wrong result Problem: null_value was checked before calling val_str(), so null_value corresponded NULL flag for the previous row. Fix: don't check null_value before calling val_str(), val_str itself returns NULL in case of NULL result.
[18 Mar 2008 13:00]
Alexander Barkov
Pushed into 6.0.5-engines
[27 Mar 2008 17:49]
Bugs System
Pushed into 6.0.5-alpha
[27 Mar 2008 18:56]
Paul DuBois
Noted in 6.0.5 changelog. The WEIGHT_STRING() function returned incorrect results for column values when earlier column values were NULL.
Description: I create a table with a VARCHAR column. I insert two rows: NULL and 'a'. I select, making sure to find NULL first. The weight_string() function returns NULL twice. How to repeat: mysql> create table t (s1 varchar(5)); Query OK, 0 rows affected (0.01 sec) mysql> insert into t values ('a'),(null); Query OK, 2 rows affected (0.00 sec) Records: 2 Duplicates: 0 Warnings: 0 mysql> select hex(weight_string(s1)) from t order by s1; +------------------------+ | hex(weight_string(s1)) | +------------------------+ | NULL | | NULL | +------------------------+ 2 rows in set (0.00 sec)