DB2 - Problembeschreibung
Problem IC70680 | Status: Geschlossen |
SERVER OPTIONS NEED TO BE ADDED TO ADJUST COST ESTIMATION FOR FETCHING DATA FROM REMOTE SERVER IN CERTAIN ENVIRONMENT | |
Produkt: | |
DB2 FOR LUW / DB2FORLUW / 970 - DB2 | |
Problembeschreibung: | |
In certain environment, cost for fetching massive rows from remote server is over-cost, while execution of a remote statement multi-times is under-cost. As a result, IFS chooses a NLJN which fetches remote data for multi-times, instead of choosing the HSJN which fetches all data of a remote table at one time, and the performance could be bad with the NLJN. | |
Problem-Zusammenfassung: | |
Problem Description: SERVER OPTIONS NEED TO BE ADDED TO ADJUST COST ESTIMATION FOR FETCHING DATA FROM REMOTE SERVER IN CERTAIN ENVIRONMENT Problem Summary: In certain environment, cost for fetching massive rows from remote server is over-cost, while execution of a remote statement multi-times is under-cost. As a result, IFS chooses a NLJN which fetches remote data for multi-times, instead of choosing the HSJN which fetches all data of a remote table at one time, and the performance could be bad with the NLJN. | |
Local-Fix: | |
Use plan hints, explicit selectivity, stats views to force the HSJN plan. | |
verfügbare FixPacks: | |
DB2 Version 9.7 Fix Pack 4 for Linux, UNIX, and Windows | |
Lösung | |
Problem is first fixed in Version 9.7 Fixpack 4 | |
Workaround | |
Use plan hints, explicit selectivity, stats views to force the HSJN plan. | |
Weitere Daten | |
Datum - Problem gemeldet : Datum - Problem geschlossen : Datum - der letzten Änderung: | 20.08.2010 28.02.2011 28.02.2011 |
Problem behoben ab folgender Versionen (IBM BugInfos) | |
9.7.FP4 | |
Problem behoben lt. FixList in der Version | |
9.7.0.4 |