DB2 FOR LUW / DB2FORLUW / 970 - DB2

DB2 Query ReWrite may be able to improve the performance of a 
query by optimizing it during compilation if it satisfies the 
following conditions: 
- The query refers to 2 or more UNION ALL views (UAV) 
- Each UAV branch or operand is one of the following: 
(a) a select over a base table 
(b) an anti-join between 2 base tables (using a not-exists 
subquery) 
(c) an inner, left or right outer join of any combination of (a) 
or (b) 
(d) an inner, left or right outer join of any combination of 
(a), (b) or (c) 
- The UAVs are joined to each other 
- The joins between the UAVs are either all inner joins or joins 
on columns that source from row-preserving sides of any outer 
joins 
 
This enhancement is only available under registry variable 
control. To enable it, issue: 
db2set 
DB2_UNION_OPTIMIZATION=[<other-values>,] 
ENABLE_NESQ_PD_THRU_UA=YES 
[,<other-values>] 
and restart the database manager for settings to take effect.

**************************************************************** 
* USERS AFFECTED:                                              * 
* ALL                                                          * 
**************************************************************** 
* PROBLEM DESCRIPTION:                                         * 
* See Error Description.                                       * 
**************************************************************** 
* RECOMMENDATION:                                              * 
* Upgrade to DB2 Version 9.7 Fix Pack 5 or later.              * 
****************************************************************

Manually rewrite any applicable queries to be of the form 
derived through this enhancement.

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 8 for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 9 for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 9a for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 10 for Linux, UNIX, and Windows
 

First fixed in DB2 Version 9.7 Fix Pack 5.

keiner bekannt / siehe Local-Fix

Datum - Problem gemeldet    :
Datum - Problem geschlossen :
Datum - der letzten Änderung:

25.04.2011
31.01.2012
12.03.2012

9.7.FP5