DB2 FOR LUW / DB2FORLUW / A10 - DB2

DB2 might return extra rows when there is a combination of an 
equal join predicate between columns and those same columns 
equijoined to non-cast expressions, like COALESCE or VALUE 
function. 
The following pseudo statement illustrates one of example to hit 
the condition. 
 
select 
 from 
 (select 
   value(c1, x) as c1 
   c2 ... ) as t1 
 inner join 
 (select 
   value(c1, x) as c1 
   c2 ....) as t2 
 on 
   t1.c1 = t2.c1 
 
This problem exists in v10.1 only, and HSJOIN needs to be 
involved.

**************************************************************** 
* USERS AFFECTED:                                              * 
* Users who run SQLs described in the APAR text.               * 
**************************************************************** 
* PROBLEM DESCRIPTION:                                         * 
* See Error Description                                        * 
**************************************************************** 
* RECOMMENDATION:                                              * 
* Please upgrade to DB2 V10.1 Fixpack 4 or later.              * 
****************************************************************

Please set DB2_REDUCED_OPTIMIZATION=NO_HJEXP to bypass this 
issue. 
The -im option allows users not to restart the instance, but 
drive to compile the query. 
 
db2set DB2_REDUCED_OPTIMIZATION=NO_HJEXP -im

DB2 Version 10.1 Fix Pack 4 for Linux, UNIX, and Windows
 DB2 Version 10.1 Fix Pack 6 for Linux, UNIX, and Windows
 

This problem was first fixed in DB2 V10.1 Fixpack 4.

not known / see Local fix

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

20.03.2014
09.06.2014
09.06.2014