DB2 FOR LUW / DB2FORLUW / A50 - DB2

Under rare scenarios, DB2 might produce an incorrect result if 
the following conditions are true: 
1) The query contains a NULL constant in predicate 
2) The predicate is of the form expression <relop> NULL where 
<relop> can be =,>=,<= 
3) The expression is either a CASE expression or a NULLIF 
function 
4) The output of the expression is guaranteed to be NULL 
 
eg. 
select * from t1 where NULLIF (c1, c1) >= Cast(NULL as int); 
select * from t1 where case when c1 = c1 then NULL else c1 end 
>= cast(NULL as BIGINT);

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* USERS AFFECTED:                                              * 
* All users                                                    * 
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* PROBLEM DESCRIPTION:                                         * 
* See Error Description                                        * 
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* RECOMMENDATION:                                              * 
* Upgrade to DB2 version 10.5.0.4.                             * 
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1) drop the redundant predicate 
2) Change the query optimization level to 0

DB2 Cancun Release 10.5.0.4 (also known as Fix Pack 4) for Linux, UNIX, and Windows
 DB2 Version 10.5 Fix Pack 9 for Linux, UNIX, and Windows
 

The problem is first fixed in DB2 version 10.5.0.4.

not known / see Local fix

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

08.05.2014
08.09.2014
21.04.2015