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IC80536: QUERY RETURNS INCORRECT RESULTS FOR A CORRELATED SUBQUERY AGAINST A DATA PARTITIONED TABLE.

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You can track all active APARs for this component.

APAR status

  • Closed as fixed if next.

Error description

  • If the access plan for a correlated subquery contains a nested
    loop join with a partitioned table on the inner side of the
    join, and if the join predicate AND the correlated predicate are
    pushed down into the scan of the partitioned table, then it's
    possible that wrong results may occur.
    
    The defect is a logic problem during query runtime where data
    partitions are incorrectly eliminated from the scan, resulting
    in the scan failing to qualify records that should have
    otherwise been found.
    

Local fix

  • Since the problem is dependent upon the above mentioned access
    plan, it may be possible to get an alternate access plan that
    avoids the problematic codepath in runtime.
    

Problem summary

  • If the access plan for a correlated subquery contains a nested
    loop join with a partitioned table on the inner side of the
    join, and if the join predicate AND the correlated predicate are
    pushed down into the scan of the partitioned table, then it's
    possible that wrong results may occur.
    
    The defect is a logic problem during query runtime where data
    partitions are incorrectly eliminated from the scan, resulting
    in the scan failing to qualify records that should have
    otherwise been found.
    
    First fixed in DB2 Version 9.7 Fix Pack 6
    

Problem conclusion

Temporary fix

  • Since the problem is dependent upon access
    plan, it may be possible to get an alternate access plan that
    avoids the problematic codepath in runtime.
    

Comments

APAR Information

  • APAR number

    IC80536

  • Reported component name

    DB2 FOR LUW

  • Reported component ID

    DB2FORLUW

  • Reported release

    970

  • Status

    CLOSED FIN

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt

  • Submitted date

    2011-12-20

  • Closed date

    2013-04-19

  • Last modified date

    2013-04-19

  • APAR is sysrouted FROM one or more of the following:

    IC80535

  • APAR is sysrouted TO one or more of the following:

Fix information

Applicable component levels

  • R970 PSY

       UP



Document information

More support for: DB2 for Linux, UNIX and Windows

Software version: 9.7

Reference #: IC80536

Modified date: 19 April 2013