DB2 - Problem description
Problem IT31233 | Status: Closed |
BAD PERFORMANCE DUE TO DELAYED JOIN PREDICATE PUSHDOWN THROUGH UNION ALL PREVENTS JOIN ELIMINATION | |
product: | |
DB2 FOR LUW / DB2FORLUW / B50 - DB2 | |
Problem description: | |
Db2 query may perform slowly when the following conditions are met: -The query has multiple joins. -One or more joins are on UNIONs on large number of tables. -There are check constraints defined on the tables used with UNION. -There are one or more predicates that may filter out one or more tables from the UNIONs. | |
Problem Summary: | |
**************************************************************** * USERS AFFECTED: * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * **************************************************************** | |
Local Fix: | |
Solution | |
Workaround | |
**************************************************************** * USERS AFFECTED: * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * **************************************************************** | |
Timestamps | |
Date - problem reported : Date - problem closed : Date - last modified : | 11.12.2019 16.09.2020 16.09.2020 |
Problem solved at the following versions (IBM BugInfos) | |
Problem solved according to the fixlist(s) of the following version(s) |