DB2 FOR LUW / DB2FORLUW / 980 - DB2

The optimizer may favor a unique index that is fully qualified 
over another unique index that is not fully qualified having 
more columns.  This may be true, even if the second index offers 
index only access. 
 
(Fully qualified means that all the columns of the index have 
equality predicates and when specified through a join, all the 
join predicates have to be between the same tables.)

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* USERS AFFECTED:                                              * 
* All.                                                         * 
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* PROBLEM DESCRIPTION:                                         * 
* See above.                                                   * 
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* RECOMMENDATION:                                              * 
* Upgrade to version 9.8 Fix Pack 3 or a later release that    * 
* includes the fix.                                            * 
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Build unique indexes that are a superset of smaller unique 
indexes using include columns: 
 
For Example, if the original definition was: 
 
   unique index1 (a) 
   unique index2 (a,b,c) 
 
 
 
In the above example, index2 is really unique on column a, so 
columns b and c are not needed to be part of the unique 
definition.  The second index could be defined as: 
 
   unique index2 (a) include (b,c)

DB2 Version 9.8 Fix Pack 3 for Linux, UNIX, and Windows
 DB2 Version 9.8 Fix Pack 4 for AIX and Linux
 DB2 Version 9.8 Fix Pack 5 for AIX and Linux
 

Problem was first fixed in Version 9.8 Fix Pack 3.

keiner bekannt / siehe Local-Fix

Datum - Problem gemeldet    :
Datum - Problem geschlossen :
Datum - der letzten Änderung:

20.04.2010
22.12.2010
22.12.2010

9.8.FP3