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Problem IC85858
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Status: Closed |
INCONSISTENCY IN FILTER FACTOR CALCULATION FOR RANGE PREDICATES VALUES THAT ARE BEYOND THE LAST HISTOGRAM |
| product: |
DB2 FOR LUW / DB2FORLUW / 970 - DB2 |
| Problem description: |
When range predicate literal values are beyond the highest
quantile value, filter factor calculation may be incorrect.
For example, suppose the highest quantile value for the column
DATE is '2012-07-25'. Range predicates (DATE >= '2012-07-25' and
DATE < '2012-07-26') can result in a combined FF of almost 0
rather than the FF of the equality predicate DATE =
'2012-07-25'. |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* All *
****************************************************************
* PROBLEM DESCRIPTION: *
* See Error Description *
****************************************************************
* RECOMMENDATION: *
* Update to v9.7 Fix Pack 8 *
**************************************************************** |
| Local Fix: |
Use an equality predicate if it is logically equivalent to a set
of range predicates |
| available fix packs: |
DB2 Version 9.7 Fix Pack 8 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 9 for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 9a for Linux, UNIX, and Windows
DB2 Version 9.7 Fix Pack 10 for Linux, UNIX, and Windows
|
| Solution |
First fixed in v9.7 Fix Pack 8 |
| Workaround |
not known / see Local fix |
| BUG-Tracking |
forerunner : APAR is sysrouted TO one or more of the following: IC85887
follow-up : |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 13.08.2012
15.04.2013
15.04.2013 |
| Problem solved at the following versions (IBM BugInfos) |
9.7.FP8
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 9.7.0.8
|
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