Bug #4067 UNION query truncates fields
Submitted: 9 Jun 2004 1:33 Modified: 17 Jun 2004 14:54
Reporter: [ name withheld ]
Status: Closed
Category:Server Severity:S2 (Serious)
Version:4.1.3 OS:Linux (linux redhat fedora core2)
Assigned to: Bugs System Target Version:

[9 Jun 2004 1:33] [ name withheld ] 
Description:
UNION queries having one part of the UNION a string, and another part of the UNION an
integer, will truncate the integer to the number of characters in the string.  This
happens for both MyISAM and InnoDB.

How to repeat:
CREATE TABLE test (uid int(1))Type=MyISAM;
INSERT INTO test SELECT 150;
SELECT 'a' UNION SELECT uid FROM test;
[9 Jun 2004 1:45] Dean Ellis 
I cannot repeat this with 4.1.3.  This does occur in 4.0 (it could only be fixed in 4.1),
so could you verify your version?
[9 Jun 2004 15:57] [ name withheld ] 
To be sure, I un-installed 4.1.2-alpha and compiled 4.1.3-beta from the Development Source
Tree.  Still the same result with 4.1.3-beta:

CREATE TABLE test (uid int(1))Type=MyISAM;INSERT INTO test SELECT 150;SELECT 'a' UNION
SELECT uid FROM test;

returns:
+------+
| a    |
+------+
| a    |
| 1    |
+------+

1 should be 150
[9 Jun 2004 19:02] Dean Ellis 
On 4.1.3, I get:

+------+
| a    |
+------+
| a    |
| 150  |
+------+

I cannot reproduce this unless I'm connected to 4.0...  Make sure you have the 4.1 server
binary running: SELECT VERSION();
[9 Jun 2004 20:17] [ name withheld ] 
Is there a difference between 4.1.3-beta and plain 4.1.3 you mention?  Here are the
results of your suggestion:

mysql> SELECT 'a' UNION SELECT uid FROM test;SELECT VERSION();
+------+
| a    |
+------+
| a    |
| 1    |
+------+
2 rows in set (0.00 sec)

+------------+
| VERSION()  |
+------------+
| 4.1.3-beta |
+------------+
1 row in set (0.00 sec)
[9 Jun 2004 21:12] Dean Ellis 
Verified against 4.1.3/Linux using latin1 client character set.  Does not occur with utf8
client character set.  Thank you for the report and your assistance.
[16 Jun 2004 17:07] Oleksandr Byelkin 
ChangeSet 
  1.1921 04/06/16 16:06:30 bell@sanja.is.com.ua +5 -0 
  new length detection for non-string in UNION (BUG#4067)
[17 Jun 2004 14:54] Oleksandr Byelkin 
Thank you for bug report. patch is pushed in our internal repository and will 
be present in next server release.