DB2 FOR LUW / DB2FORLUW / A50 - DB2

The DB2 optimizer might produce a non-optimal access plan, in a 
DPF environment, for SQL statements under the following 
conditions: 
 
1. The SQL statement includes two or more local equality 
predicates applied to a table distributed across multiple 
database partitions 
2. The local equality predicates reference literal values, 
including variable values when REOPT is enabled, that are 
infrequent or don't exist 
3. There is a column group statistic or index that covers the 
local equality predicates 
 
Under these conditions, the optimizer will correctly estimate 
the individual filter factors of the local equality predicates, 
but it will use the index or column group statistics to account 
for statistical correlation.  In doing so, the optimizer might 
over-estimate the cardinality which could lead to a 
non-optimal access plan being chosen.

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* USERS AFFECTED:                                              * 
* ALL                                                          * 
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* PROBLEM DESCRIPTION:                                         * 
* See Error Description                                        * 
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* RECOMMENDATION:                                              * 
* Upgrade to  DB2 V10.5 FP 7                                   * 
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First Fixed in DB2 V10.5 FP 7

not known / see Local fix

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

01.05.2015
19.01.2016
19.01.2016