DB2 FOR LUW / DB2FORLUW / B10 - DB2

If SQL against COLUMNAR table has 2 predicates , one of them 
CASE and part of the CASE or entire CASE condition matches the 
other predicate, then we could eliminate the second predicate by 
mistake. 
 
Example: 
 
SELECT * FROM T WHERE ( SUBSTR(A,1,1) = 'B' ) AND CASE WHEN ( 
SUBSTR(A,1,1) = 'B' ) THEN B ELSE B END <> 0 
 
( SUBSTR(A,1,1) = 'B' ) is used as it's own predicate AND as 
condition in CASE statement. 
 
In some cases we could lose this predicate and only apply CASE 
WHEN ( SUBSTR(A,1,1) = 'B' ) THEN B ELSE B END <> 0 which will 
return extra rows.

**************************************************************** 
* USERS AFFECTED:                                              * 
* ALL                                                          * 
**************************************************************** 
* PROBLEM DESCRIPTION:                                         * 
* See Error Description                                        * 
**************************************************************** 
* RECOMMENDATION:                                              * 
* Upgrade to Db2 11.1 Mod 2 Fix Pack 2 iFix001 or higher       * 
****************************************************************

rewrite query to avoid this situation or install this fix.

Db2 Version 11.1 Mod2 Fix Pack2 iFix001 for Linux, UNIX, and Windows
 Db2 Version 11.1 Mod2 Fix Pack2 iFix002 for Linux, UNIX, and Windows
 Db2 Version 11.1 Mod 3 Fix Pack 3 for Linux, UNIX, and Windows
 Db2 Version 11.1 Mod3 Fix Pack3 iFix001 for Linux, UNIX, and Windows
 Db2 Version 11.1 Mod3 Fix Pack3 iFix002 for Linux, UNIX, and Windows
 

First fixed in Db2 11.1 Mod 2 Fix Pack 2 iFix001

not known / see Local fix

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

26.05.2017
11.10.2017
12.10.2017