DB2 FOR LUW / DB2FORLUW / A10 - DB2

Under rare scenarios, performance degradation might be noticed 
if the following conditions are true: 
 
1. There is a sequence present in the output column of select 
list 
2. There are two or more tables in the subselect directly below 
the sequence 
 
eg. 
select SEQUENCE1.NEXTVAL, col1, col2 
from table1 t1 
where t1.col1 = 
   (select MAX(col1) 
   from table1 t1 
   where col2 = ?);

**************************************************************** 
* USERS AFFECTED:                                              * 
* All Users on DB2 v10.1 FP2 and lower                         * 
**************************************************************** 
* PROBLEM DESCRIPTION:                                         * 
* See Error Description                                        * 
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* RECOMMENDATION:                                              * 
* Upgrade to DB2 v10.1 FP3                                     * 
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Separate the sequence into a new subselect: 
 
select SEQUENCE1.NEXTVAL , col1, col2 
from 
(select * 
from table1 t1 
where t1.col1 = 
   (select MAX(col1) 
   from table1 t1 
   where col2 = ?);

First Fixed in DB2 v10.1 FP3

not known / see Local fix

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

21.01.2013
10.10.2017
10.10.2017