MF68748 - OSP-DB-OTHER-PERFM SQL HIGH CPU JOIN SKEW

TYPE PROGRAM  RELEASE   NUMBER   MIN/MAX  OPTION
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NONE



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APAR Error Description / Circumvention

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The statistics engine provides a poor estimate for a join after
expecting skewed data on the join, despite having related local
predicates that should prevent the skewed value from joining.
The bad estimate results in a poorly performing plan.

CORRECTION FOR APAR MA49069 :
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In certain code paths, the statistics engine is using an
incorrect padding value for graphic unicode fields, which leads
to an invalid comparison between variables and a poor estimate.

CIRCUMVENTION FOR APAR MA49069 :
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None.


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Supersedes

PTF/FIX NO(S).  APAR TITLE LINE
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Summary Information

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