DB2 - Problem description
Problem IC89609 | Status: Closed |
PERFORMANCE DEGRADATION WHEN SEQUENCE IS PRESENT IN THE SELECT LIST COLUMN | |
product: | |
DB2 FOR LUW / DB2FORLUW / 970 - DB2 | |
Problem description: | |
Under rare scenarios, performance degradation might be noticed if the following conditions are true: 1. There is a sequence present in the output column of select list 2. There are two or more views in the subselect directly below the sequence eg. select SEQUENCE1.NEXTVAL, col1, col2 from view1 v1 where v1.col1 = (select MAX(col1) from view1 v1 where col2 = ?); | |
Problem Summary: | |
**************************************************************** * USERS AFFECTED: * * All users on DB2 v97 FP8 and lower * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Upgrade to DB2 V97 FP9 * **************************************************************** | |
Local Fix: | |
Separate the sequence into a new subselect: select SEQUENCE1.NEXTVAL , col1, col2 from (select * from view1 v1 where v1.col1 = (select MAX(col1) from view1 v1 where col2 = ?)); | |
available fix packs: | |
DB2 Version 9.7 Fix Pack 9 for Linux, UNIX, and Windows | |
Solution | |
First Fixed in DB2 V97 FP9 | |
Workaround | |
not known / see Local fix | |
BUG-Tracking | |
forerunner : APAR is sysrouted TO one or more of the following: IC89670 IC91783 follow-up : | |
Timestamps | |
Date - problem reported : Date - problem closed : Date - last modified : | 17.01.2013 17.12.2013 17.12.2013 |
Problem solved at the following versions (IBM BugInfos) | |
9.7.FP9 | |
Problem solved according to the fixlist(s) of the following version(s) | |
9.7.0.9 | |
9.7.0.9 |