DB2 - Problembeschreibung
Problem IT08268 | Status: Geschlossen |
DB2 MIGHT PERFORM POORLY FOR SUBQUERY CONTAINING CORRELATED SELECT LIST EXPRESSIONS AND COLUMN ORGANIZED TABLES | |
Produkt: | |
DB2 FOR LUW / DB2FORLUW / A50 - DB2 | |
Problembeschreibung: | |
Under rare scenarios, DB2 might produce a suboptimal plan if the following conditions are true: 1) The query contains one or more subqueries 2) The subquery is either a NOT EXISTS subquery or of the form EXISTS OR EXISTS 3) At least one subquery contains one or more column organized tables 4) The subquery also contains a correlated reference to the outer subselect in the select list expression eg. Select * from T1 where EXISTS (select T1.c1 from T2 where T1.C1 = T2.C1) OR EXISTS (select T3.c1 from T3 where T1.C1 = T3.C1) | |
Problem-Zusammenfassung: | |
**************************************************************** * USERS AFFECTED: * * All * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Upgrade to DB2 version 10.5.0.7 * **************************************************************** | |
Local-Fix: | |
Replace the correlated reference with constant 1 in the select list. Select * from T1 where EXISTS (select 1 from T2 where T1.C1 = T2.C1) OR EXISTS (select 1 from T3 where T1.C1 = T3.C1) | |
Lösung | |
Fixed in DB2 version 10.5.0.7 | |
Workaround | |
keiner bekannt / siehe Local-Fix | |
Weitere Daten | |
Datum - Problem gemeldet : Datum - Problem geschlossen : Datum - der letzten Änderung: | 13.04.2015 05.02.2016 05.02.2016 |
Problem behoben ab folgender Versionen (IBM BugInfos) | |
Problem behoben lt. FixList in der Version | |
10.5.0.7 |