|
Problem IC78217
|
Status: Closed |
SMALL DECLARED TEMPORARY TABLES IN DPF MIGHT HAVE POOR QUERY ACCESS PLAN |
| product: |
DB2 FOR LUW / DB2FORLUW / 950 - DB2 |
| Problem description: |
In a DPF environment, when a declared temporary table is created
into a multi-dbpartition tablespace, data skew might lead to a
situation where some dbpartitions do not have data. This
situation is more likely to occur when the table is small. If
statistics collection is performed from a dbpartition with no
data, the query optimizer will plan the query based on the table
being empty, which might lead to a poor access plan.
This problem was first introduced in DB2 Version 9.5 Fix Pack 6. |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* ALL *
****************************************************************
* PROBLEM DESCRIPTION: *
* SMALL DECLARED TEMPORARY TABLES IN DPF MIGHT HAVE POOR QUERY *
* ACCESS PLAN *
****************************************************************
* RECOMMENDATION: *
* Upgrade to DB2 Version 9.5 Fix Pack 9. *
**************************************************************** |
| Local Fix: |
Use a single dbpartition tablespace for small declared temporary
tables. |
| available fix packs: |
DB2 Version 9.5 Fix Pack 9 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 10 for Linux, UNIX, and Windows
|
| Solution |
First fixed in DB2 version 9.5 Fixpack 9. |
| Workaround |
not known / see Local fix |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 18.08.2011
10.04.2012
10.04.2012 |
| Problem solved at the following versions (IBM BugInfos) |
9.5.FP9
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 9.5.0.9
|
 |
