DB2 FOR LUW / DB2FORLUW / 970 - DB2

Concurrently executing CREATE OR REPLACE view statements for two 
different already created views, may deadlock. 
 
This APAR can be identified by using the locking event monitor 
with history to capture which locks are involved in the 
deadlock.  If the event monitor output shows that both 
participants are executing CREATE OR REPLACE VIEW statements, 
and one of the locks involved in the deadlock is a record (row) 
lock from SYSIBM.SYSCOLAUTH where the requester is attempting to 
obtain a U-lock, then this APAR will address this issue.

**************************************************************** 
* USERS AFFECTED:                                              * 
* All DB2 for Linux, Unix and Windows servers Version 9.7 GA   * 
* through to Fix Pack 1 issuing CREATE OR REPLACE view         * 
* statements concurrently.                                     * 
**************************************************************** 
* PROBLEM DESCRIPTION:                                         * 
* Deadlocks may occur with concurrently issued CREATE OR       * 
* REPLACE view statements on different views.  The problem is  * 
* with the database manager locking strategy when making       * 
* system catalog table updates to perform this DDL.  More      * 
* precisely, locking strategies involving the                  * 
* SYSIBM.SYSCOLAUTH were too harsh leading to potential        * 
* deadlock scenarios.                                          * 
**************************************************************** 
* RECOMMENDATION:                                              * 
* See local fix, or apply DB2 Version 9.7 Fix Pack 2.          * 
****************************************************************

Run CREATE OR REPLACE view statements serially if possible. 
Also, issuing a DROP VIEW followed by a CREATE VIEW statement 
instead of CREATE OR REPLACE should lessen the chances for 
deadlocks.  You can also modify the application to handle 
deadlocks gracefully, and re-issue the statements as necessary.

DB2 Version 9.7 Fix Pack 2 for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 3 for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 3a for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 4 for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 5 for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 6 for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 7 for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 9a for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 8 for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 9 for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 10 for Linux, UNIX, and Windows
 

Problem is first fixed in DB2 Version 9.7 Fix Pack 2 and all 
subsequent Fix Packs.

not known / see Local fix

forerunner  : APAR is sysrouted TO one or more of the following: IC67716 
follow-up : 

Date  - problem reported    :
Date  - problem closed      :
Date  - last modified       :

07.04.2010
10.06.2010
10.06.2010

9.7.FP2