Bug #38054 "SET SESSION debug" modifies @@global.debug variable
Submitted: 11 Jul 2008 18:23 Modified: 20 May 2010 15:11
Reporter: Gleb Shchepa Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Server: General Severity:S3 (Non-critical)
Version:6.0 only OS:Any
Assigned to: Alexander Nozdrin CPU Architecture:Any
Tags: regression

[11 Jul 2008 18:23] Gleb Shchepa
Description:
Server version: 6.0.6-alpha-debug Source distribution

mysql> SELECT @@session.debug, @@global.debug;
+-----------------+----------------+
| @@session.debug | @@global.debug |
+-----------------+----------------+
|                 |                | 
+-----------------+----------------+
1 row in set (0.00 sec)

mysql> SET SESSION debug="d,blablabla";
Query OK, 0 rows affected (0.00 sec)

mysql> SELECT @@session.debug, @@global.debug;
+-----------------+----------------+
| @@session.debug | @@global.debug |
+-----------------+----------------+
| d,blablabla     | d,blablabla    | 
+-----------------+----------------+
1 row in set (0.00 sec)

How to repeat:
--source include/have_debug.inc
SELECT @@session.debug, @@global.debug;
SET SESSION debug="d,blablabla";
SELECT @@session.debug, @@global.debug;
[11 Jul 2008 18:45] Sveta Smirnova
Thank you for the report.

Verified as described.
[11 Jul 2008 19:16] MySQL Verification Team
Adding flag regression 6.0.2 doesn't presents this behavior:

C:\temp\mysql-6.0.2-alpha-win32>bin\mysql -uroot
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 6.0.2-alpha-community-nt-debug MySQL Community Server (GPL)

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> SELECT @@session.debug, @@global.debug;
+-----------------+----------------+
| @@session.debug | @@global.debug |
+-----------------+----------------+
|                 |                |
+-----------------+----------------+
1 row in set (0.02 sec)

mysql> SET SESSION debug="d,blablabla";
Query OK, 0 rows affected (0.00 sec)

mysql> SELECT @@session.debug, @@global.debug;
+-----------------+----------------+
| @@session.debug | @@global.debug |
+-----------------+----------------+
| d,blablabla     |                |
+-----------------+----------------+
1 row in set (0.03 sec)
[11 Jul 2008 19:21] MySQL Verification Team
Version 5.1 isn't affected by this bug.

C:\dbs>c:\dbs\5.1\bin\mysql -uroot --port=3510 --prompt="mysql 5.1 >"
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.1.28-nt-debug-log Source distribution

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql 5.1 >SELECT @@session.debug, @@global.debug;
+-----------------+----------------+
| @@session.debug | @@global.debug |
+-----------------+----------------+
|                 |                |
+-----------------+----------------+
1 row in set (0.00 sec)

mysql 5.1 >SET SESSION debug="d,blablabla";
Query OK, 0 rows affected (0.05 sec)

mysql 5.1 >SELECT @@session.debug, @@global.debug;
+-----------------+----------------+
| @@session.debug | @@global.debug |
+-----------------+----------------+
| d,blablabla     |                |
+-----------------+----------------+
1 row in set (0.02 sec)

mysql 5.1 >
[6 Mar 2009 10:05] Bjørn Munch
This is now blocking the use of --debug with the new MTR on 6.0, see Bug #43405.
[10 Mar 2009 14:39] Alexander Nozdrin
The following bugs are duplicates of this one:
  - Bug#42892
  - Bug#42889
  - Bug#42891
[12 Mar 2009 9:46] Alexander Nozdrin
Correction: Bug#42889 and Bug#42891 are not duplicates of this one.
[25 Mar 2009 16:51] 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/70389

2748 Alexander Nozdrin	2009-03-25
      Patch for Bug#38054: "SET SESSION debug" modifies @@global.debug variable.
      
      1. Fix merge error.
      2. Add a test case to ensure it will not be broken in the future.
[25 Mar 2009 16:53] Alexander Nozdrin
Pushed into 6.0-runtime.
[31 Mar 2009 14:22] Bugs System
Pushed into 6.0.11-alpha (revid:davi.arnaut@sun.com-20090331130058-yonsevjt1833wt5o) (version source revid:alik@sun.com-20090325165128-et2eti9fvlzjsvzi) (merge vers: 6.0.11-alpha) (pib:6)
[3 Apr 2009 2:43] Paul Dubois
Noted in 6.0.11 changelog.

Setting the session value of the debug system variable also set the 
global value.
[19 May 2010 12:31] 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/108620

3050 Alexander Nozdrin	2010-05-19
      Backport test cases for Bug#46198 and Bug#38054
      from 6.0 to trunk-bugfixing.
[20 May 2010 10:04] Bugs System
Pushed into 6.0.14-alpha (revid:alik@sun.com-20100520100225-oe4iuu5kuzsx0knq) (version source revid:alik@sun.com-20100520100057-rmn5y3o3ij726bm7) (merge vers: 6.0.14-alpha) (pib:16)
[20 May 2010 10:05] Bugs System
Pushed into 5.5.5-m3 (revid:alik@sun.com-20100520100041-rf8ujv598zf86wjt) (version source revid:alik@sun.com-20100520100041-rf8ujv598zf86wjt) (merge vers: 5.5.5-m3) (pib:16)
[20 May 2010 10:06] Bugs System
Pushed into mysql-next-mr (revid:alik@sun.com-20100520100140-5bzrtadw4w419i3m) (version source revid:alik@sun.com-20100520100049-1njm09rkvnhmysnr) (pib:16)
[20 May 2010 15:11] Paul Dubois
Noted in 5.5.5 changelog.