DB2 - Problem description
Problem IC97775 | Status: Closed |
INSTANCE MIGHT ABEND OR RETURN INCORRECT RESULTS DUE TO AN INCORRECT EXECUTION SECTION FOR STAR JOIN | |
product: | |
DB2 FOR LUW / DB2FORLUW / A10 - DB2 | |
Problem description: | |
An instance might abend or return incorrect results under some very specific access plan conditions. A typical trap file might show the following functions at the top of the stacktrace report: sqlriREBAL2 sqldEvalDataPred sqldReadTemp sqldfrd sqldRowFetch sqlsfetc sqlriFetch sqlriNljnNonPiped sqlrihsjn sqlriSectInvoke The problem is due to an incorrect buffer location that is being accessed. This can only be confirmed by db2 service personnel by examining the "section dump" of the execution plan. The "section dump" is located in the binary dump file. From an access plan point of view, at least the following conditions must be true: - There is a star join that has a join of a dimension table above the IXAND operator that references the same columns of the dimension table that was already accessed in the star join below the IXAND operator. This might also be referred to as a back join. - The dimension table column that is accessed in the star join and also later used in the back join is accessed by the Data Sargable Predicate and the column. The dimension table column must also not be added to the Output Stream of the Table Scan. | |
Problem Summary: | |
**************************************************************** * USERS AFFECTED: * * All users * **************************************************************** * PROBLEM DESCRIPTION: * * See Error Description * **************************************************************** * RECOMMENDATION: * * Upgrade to DB2 version 10.1.0.4. * **************************************************************** | |
Local Fix: | |
There is no known workaround for this problem other than to force a different access plan to avoid at least one of the above conditions. | |
available fix packs: | |
DB2 Version 10.1 Fix Pack 4 for Linux, UNIX, and Windows | |
Solution | |
The problem is first fixed in DB2 version 10.1.0.4. | |
Workaround | |
not known / see Local fix | |
Timestamps | |
Date - problem reported : Date - problem closed : Date - last modified : | 19.11.2013 08.05.2014 26.05.2014 |
Problem solved at the following versions (IBM BugInfos) | |
Problem solved according to the fixlist(s) of the following version(s) | |
10.1.0.4 |