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Bug #35588 Incorrect work with character sets in stored functions
Submitted: 27 Mar 2008 3:51 Modified: 2 May 2008 17:23
Reporter: Mikhail Serov Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Server: Charsets Severity:S2 (Serious)
Version:5.0.22-log OS:Linux
Assigned to: CPU Architecture:Any
Tags: character sets, stored routines

[27 Mar 2008 3:51] Mikhail Serov 
Description:
Data from string columns with non-latin characters are treated incorrectly in stored functions.

Note: stored procedures seem to behave correctly.
Note 2: MySQL server on Windows looks like free from this bug

mysql> use test
Database changed

mysql> SET NAMES utf8;
Query OK, 0 rows affected (0.02 sec)

mysql> CREATE TABLE tbl (utf8column VARCHAR(255) COLLATE utf8_general_ci);
Query OK, 0 rows affected (0.02 sec)

mysql> INSERT INTO tbl VALUES ('latin characters русские буквы');
Query OK, 1 row affected (0.00 sec)

mysql> SELECT * FROM tbl\G
*************************** 1. row ***************************
utf8column: latin characters русские буквы
1 row in set (0.00 sec)

mysql> CREATE FUNCTION utf8function () RETURNS VARCHAR(255) CHARACTER SET utf8 DETERMINISTIC
    -> RETURN (SELECT utf8column FROM tbl LIMIT 1);
Query OK, 0 rows affected (0.03 sec)

mysql> SELECT utf8function() /* Here questions marks appear */;
+--------------------------------+
| utf8function()                 |
+--------------------------------+
| latin characters ??????? ????? |
+--------------------------------+
1 row in set, 1 warning (0.00 sec)

mysql> SHOW WARNINGS;
+---------+------+-----------------------------------------------------+
| Level   | Code | Message                                             |
+---------+------+-----------------------------------------------------+
| Warning | 1265 | Data truncated for column 'utf8function()' at row 1 |
+---------+------+-----------------------------------------------------+
1 row in set (0.00 sec)

How to repeat:
use test;
SET NAMES utf8;
CREATE TABLE tbl (utf8column VARCHAR(255) COLLATE utf8_general_ci);
INSERT INTO tbl VALUES ('latin characters русские буквы');
SELECT * FROM tbl\G
CREATE FUNCTION utf8function () RETURNS VARCHAR(255) CHARACTER SET utf8 DETERMINISTIC
RETURN (SELECT utf8column FROM tbl LIMIT 1);
SELECT utf8function() /* Here questions marks appear */;
SHOW WARNINGS;
[27 Mar 2008 6:53] Valeriy Kravchuk 
Thank you for a problem report. Please, try to repeat with a newer version, 5.0.51a, and inform about the results.

In case of the same problem, please, send the results of:

show variables like 'char%'\G

and 

echo $LANG from shell.
[27 Apr 2008 23:00] Bugs System 
No feedback was provided for this bug for over a month, so it is
being suspended automatically. If you are able to provide the
information that was originally requested, please do so and change
the status of the bug back to "Open".
[2 May 2008 8:26] Mikhail Serov 
Yes, really on 5.0.51 it worked properly.
[2 May 2008 17:23] Valeriy Kravchuk 
Bug is not repeatable with 5.0.51a.