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Problem IC70256	Status: Closed
STATVIEW COLUMN STATISTICS NOT USED FOR CARDINALITY ESTIMATE FOR COMPLEX AND/OR PREDICATES
product:
DB2 FOR LUW / DB2FORLUW / 980 - DB2
Problem description:
DB2 uses the individual column statistics to correct the cardinality estimate for predicates applied to columns in views enabled for optimization (statistical views, or statviews for short). When the predicate involves combinations of AND and OR predicates, the correction is not applied properly. For example, the statview column statistics would be used to estimate the filtering for predicates like: "column1 >= 7 and column1 <= 9", or "column1 = 7 or column1 = 9" However, it would not be used to estimate the filtering for predicates like: "column1 >= 7 and column1 <= 9 or column1 >= 15 and column1 <= 18" This fix addresses the filtering estimate for the more complex predicate with predicates combined with OR and AND.
Problem Summary:
Will not be fixed in V9.8.
Local Fix:

Solution

Workaround
not known / see Local fix
Timestamps
Date - problem reported : Date - problem closed : Date - last modified :	28.07.2010 01.12.2011 01.12.2011
Problem solved at the following versions (IBM BugInfos)

Problem solved according to the fixlist(s) of the following version(s)