DB2 - Problem description
Problem IC95241 | Status: Closed |
DB2 SQL QUERY OPTIMIZER HAS IMPROVED THE PERFORMANCE OF SIMPLE SINGLE-ROW MERGE STATEMENT | |
product: | |
DB2 FOR LUW / DB2FORLUW / A50 - DB2 | |
Problem description: | |
DB2 SQL Query Optimizer has improved the performance of merge statements when all of the following conditions are satisfied: (1) the merge source is provably single-row. It includes the cases when the merge source is: - a single row VALUES clause - a sub-SELECT with with FETCH FIRST 1 ROWS ONLY - a simple sub-select from a table with unique key columns bound to constants, host variables or parameter markers. (2) the merge target table has a unique key defined on the merge join columns (3) the join predicates in the ON clause are simple equality predicates that join columns from the source and target tables (4) the merge target table has no trigger, constraint, dependent immediate MQT or staging table (5) the merge statement has at most two WHEN clauses with only UPDATE or INSERT operations. In the case of two WHEN clauses, one operation must be an UPDATE and the other operation must be an INSERT (6) there is no additional predicate in the merge WHEN clause (7) The partitioning keys (DPF, MDC or data partitioning) are not modified by the UPDATE operation | |
Problem Summary: | |
**************************************************************** * USERS AFFECTED: * * All Platforms * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Upgrade to DB2 LUW v10.5 Fixpack 3 or Higher. * **************************************************************** | |
Local Fix: | |
available fix packs: | |
DB2 Version 10.5 Fix Pack 3 for Linux, UNIX, and Windows | |
Solution | |
First Fixed in DB2 LUW v10.5 Fixpack 3. | |
Workaround | |
not known / see Local fix | |
Timestamps | |
Date - problem reported : Date - problem closed : Date - last modified : | 27.08.2013 07.05.2014 07.05.2014 |
Problem solved at the following versions (IBM BugInfos) | |
Problem solved according to the fixlist(s) of the following version(s) | |
10.5.0.3 | |
10.5.0.3 | |
10.5.0.4 |