Bug #321 SELECT with where clause doesn't work if collation is utf8
Submitted: 24 Apr 2003 1:18 Modified: 24 Apr 2003 7:02
Reporter: [ name withheld ] Email Updates:
Status: Closed Impact on me:
Category:MySQL Server Severity:S2 (Serious)
Version:4.1 OS:Linux (Linux)
Assigned to: Alexander Barkov CPU Architecture:Any

[24 Apr 2003 1:18] [ name withheld ]
 The official binaries for 4.1.0-standard-alpha have a problem with utf8 character set. If collation on columns/table is set as utf8 select statements of the sort "select from bla where name = 'bla'" return "Wrong arguments to =".
 If the character set is left intact, the above select statements return correct results.
 Latest sources from BitKeeper have the same problem, whereas the version I've compiled from BitKeeper sources some 4 weeks ago (with --with-extra-charsets=complex --default-charset=utf8) works OK. 

How to repeat:
create table TEST(id int(11), name varchar(50)) type=MyISAM charset=utf8;
insert into TEST values(21, 'bla');
select * from TEST where name = 'bla';

result "Wrong arguments to =".
[24 Apr 2003 5:44] Alexander Keremidarski
With 4.1 compiled form BK tree at 23th Apr test case works as expected, but same problem appears in another place:

mysql> create table TEST(id int(11), name varchar(50)) type=MyISAM charset=utf8;
Query OK, 0 rows affected (0.00 sec)

 mysql> show create table `TEST`;
| Table | Create Table
  `id` int(11) default NULL,
  `name` varchar(50) default NULL
1 row in set (0.01 sec)

mysql> insert into TEST values(21, 'bla');
Query OK, 1 row affected (0.00 sec)
mysql> select * from TEST where name = 'bla';
| id   | name |
|   21 | bla  |

Query OK, 1 row affected (0.00 sec)
Records: 1  Duplicates: 0  Warnings: 0
mysql> select * from TEST where name = 'bla';
ERROR 1210: Wrong arguments to =

Now error occurs if column character set differs from table character set
[24 Apr 2003 6:33] Alexander Barkov
What does this return:

SHOW VARIABLES LIKE 'character_set%';

[24 Apr 2003 7:02] Alexander Barkov
Thank you for taking the time to write to us, but this is not
a bug. Please double-check the documentation available at
http://www.mysql.com/documentation/ and the instructions on
how to report a bug at http://bugs.mysql.com/how-to-report.php

This is not a bug. You can't compare strings in different
character sets. Your default character set is utf8.
The column uses latin1. There are two ways to
do what you want:
1. Specify that the string is in latin1 too:
SELECT * FROM test WHERE name=_latin1'bla';

2. Convert the string from utf8 to latin1:
SELECT * FROM test WHERE name=CONVERT('bla' USING latin1);

I'm closing this bug.