DB2 FOR LUW / DB2FORLUW / A10 - DB2

If a column has distribution statistics and it is the leading 
column in an index, collecting index-only statistics for the 
index will incorrectly update SYSCAT.COLUMNS.NQUANTILES and 
SYSCAT.COLUMNS.NMOSTFREQ to -1, suggesting the column does not 
have distribution statistics.  However, the column's 
distribution statistics are not affected in the 
SYSCAT.SYSCOLDIST catalog.  Also not affected are the 
distribution statistics in the table's packed descriptor which 
is used by the query optimizer. 
 
The problem therefore affects applications that query 
SYSCAT.COLUMNS.NQUANTILES and SYSCAT.COLUMNS.NMOSTFREQ, instead 
of SYSCAT.SYSCOLDIST, to determine if a column has distribution 
statistics.  The db2look tool is affected by this problem.  When 
the problem has occurred, db2look mimic output will not contain 
distribution statistics information for the affected columns.

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* USERS AFFECTED:                                              * 
* ALL                                                          * 
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* PROBLEM DESCRIPTION:                                         * 
* See Error Description                                        * 
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* RECOMMENDATION:                                              * 
* Upgrade to DB2 V10.1 FP4                                     * 
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Perform a table and indexes statistics collection on the 
affected tables.

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

Fixed in DB2 V10.1 FP4

not known / see Local fix

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

02.01.2014
09.06.2014
09.06.2014