DB2 FOR LUW / DB2FORLUW / A50 - DB2

The NUMNULLS statistics might be zero for columns that has an 
empty "EXCLUDE NULL KEYS" index. 
 
Conditions to hit this issue are : 
(1) the column is the leading column of an "EXCLUDE NULL KEYS" 
index and 
(2) the "EXCLUDE NULL KEYS" index is empty (i.e. all values are 
null) 
 
Note : Both conditions must present in order for the issue to 
occur, not only one of them.

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* USERS AFFECTED:                                              * 
* ALL                                                          * 
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* PROBLEM DESCRIPTION:                                         * 
* See Error Description                                        * 
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* RECOMMENDATION:                                              * 
* First Fixed in DB2 10.5 Fix Pack 7                           * 
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Manually update the statistics. You can use below query : 
db2 "update sysstat.columns set NUMNULLS=<expected_num_nulls> 
where colname='<column_name>' and tabname='<table_name>' and 
tabschema='<schema_name>'"

First Fixed in DB2 10.5 Fix Pack 5

not known / see Local fix

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

16.07.2015
09.05.2017
09.05.2017