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Problem IC70557
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Status: Geschlossen |
REWRITE OR PREDICATE TO UNION IN NOT IN/IN SUBQUERY MAY CAUSE PERFORMANCE REGRESSION |
| Produkt: |
DB2 FOR LUW / DB2FORLUW / 970 - DB2 |
| Problembeschreibung: |
When DB2 rewrites OR predicate to UNION to utilize an index scan
access in the context of a NOT IN or IN subquery and the
subquery has no reference to any column of the tables outside
the subquery. The result of the rewrite may cause DB2 to select
a suboptimal plan by choosing an access plan that repeats the
processing of the subquery for each row of the tables outside
the subquery. |
| Problem-Zusammenfassung: |
REWRITE OR PREDICATE TO UNION IN NOT IN/IN SUBQUERY MAY CAUSE
PERFORMANCE REGRESSION |
| Local-Fix: |
|
| verfügbare FixPacks: |
DB2 Version 9.7 Fix Pack 4 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 5 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 6 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 7 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 8 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 9 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 9a for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 10 for Linux, UNIX, and Windows
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| Lösung |
Problem was first fixed in Version 9.7 FixPack 4 |
| Workaround |
keiner bekannt / siehe Local-Fix |
| Weitere Daten |
Datum - Problem gemeldet :
Datum - Problem geschlossen :
Datum - der letzten Änderung:
| 13.08.2010
02.05.2011
02.05.2011 |
| Problem behoben ab folgender Versionen (IBM BugInfos) |
9.7.FP4
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| Problem behoben lt. FixList in der Version |
| 9.7.0.4
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