DB2 - Problem description
Problem IC75324 | Status: Closed |
SMALL DECLARED TEMPORARY TABLES IN DPF MIGHT HAVE POOR QUERY ACCESS PLAN | |
product: | |
DB2 FOR LUW / DB2FORLUW / 970 - 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 9.7 Fix Pack 2. | |
Problem Summary: | |
**************************************************************** * USERS AFFECTED: * * ALL * **************************************************************** * PROBLEM DESCRIPTION: * * SMALL DECLARED TEMPORARY TABLES IN DPF MIGHT HAVE POOR QUERY * * ACCESS PLAN * **************************************************************** * RECOMMENDATION: * * Upgrade to DB2 version 9.7 Fixpack 5. * **************************************************************** | |
Local Fix: | |
Use a single dbpartition tablespace for small declared temporary tables. | |
available fix packs: | |
DB2 Version 9.7 Fix Pack 5 for Linux, UNIX, and Windows | |
Solution | |
First fixed in DB2 version 9.7 Fixpack 5. | |
Workaround | |
not known / see Local fix | |
BUG-Tracking | |
forerunner : APAR is sysrouted TO one or more of the following: IC78217 follow-up : | |
Timestamps | |
Date - problem reported : Date - problem closed : Date - last modified : | 28.03.2011 09.01.2012 09.01.2012 |
Problem solved at the following versions (IBM BugInfos) | |
9.7.FP5 | |
Problem solved according to the fixlist(s) of the following version(s) | |
9.7.0.5 |