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Problem IC84217
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Status: Closed |
DB2 SQL QUERY COMPILER HAS IMPROVED THE PERFORMANCE OF SECONDARY TABLE ACCESSES DURING INCREMENTAL MQT MAINTENANCE IN DPF |
| product: |
DB2 FOR LUW / DB2FORLUW / A10 - DB2 |
| Problem description: |
DB2 SQL Query Compiler has improved the performance of secondary
table access for incremental maintenance of a materialized query
table (MQT) when all of the following conditions are satisfied:
(1) it is a partitioned (DPF) environment
(2) the MQT is a refresh immediate MQT or a staging table. The
MQT definition involves a join between more than one base table
(for example, T1 and T2)
(3) the SQL statement S1 being compiled is an
INSERT/UPDATE/DELETE statement that fires a trigger (Trig1).
The body of the trigger modifies one of the base tables (say,
T1) of the MQT.
(4) In the incremental MQT maintenance section of the access
plan, if the join predicate between T2 and the modified rows of
T1 could be reduced to a local predicate (i.e. a predicate that
references only T2). The reduction of the join predicate to a
local predicate may occur when the statement being compiled (S1)
or the trigger (Trig1) has specified a constant or parameter
marker for the join column of T1.
When all of the conditions above are satisfied, the evaluation
of the local predicate on T2 during incremental maintenance of
MQT will be pushed down for a more efficient access. |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* DPF customers *
****************************************************************
* PROBLEM DESCRIPTION: *
* See Error Description *
****************************************************************
* RECOMMENDATION: *
* Upgrade to DB2 version 10.1 Fix Pack 1 *
**************************************************************** |
| Local Fix: |
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| available fix packs: |
DB2 Version 10.1 Fix Pack 1 for Linux, UNIX, and Windows
DB2 Version 10.1 Fix Pack 2 for Linux, UNIX, and Windows
DB2 Version 10.1 Fix Pack 3 for Linux, UNIX, and Windows
DB2 Version 10.1 Fix Pack 4 for Linux, UNIX, and Windows
DB2 Version 10.1 Fix Pack 3a for Linux, UNIX, and Windows
DB2 Version 10.1 Fix Pack 6 for Linux, UNIX, and Windows
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| Solution |
This APAR is fixed in DB2 version 10.1 Fix Pack 1 |
| Workaround |
not known / see Local fix |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 13.06.2012
08.11.2012
08.11.2012 |
| Problem solved at the following versions (IBM BugInfos) |
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| Problem solved according to the fixlist(s) of the following version(s) |
| 10.1.0.1
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| 10.5.0.1
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