|
Problem IC66295
|
Status: Closed |
COMPRESSION STATISTIC PCTPAGESSAVED MAY BE INACCURATE. |
| product: |
DB2 FOR LUW / DB2FORLUW / 950 - DB2 |
| Problem description: |
PCTPAGESSAVED is set to 0 when RUNSTATS is executed on just the
indexes of the table via the FOR INDEXES clause, for example:
RUNSTATS ON TABLE s.t FOR INDEXES ALL
Under rare situations, incorrect intermediate calculations can
lead to an inaccurate PCTPAGESSAVED value, including 0 and
negative values. |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* ALL *
****************************************************************
* PROBLEM DESCRIPTION: *
* PCTPAGESSAVED is set to 0 when RUNSTATS is executed on just *
* the *
* indexes of the table via the FOR INDEXES clause, for *
* example: *
* *
* RUNSTATS ON TABLE s.t FOR INDEXES ALL *
* *
* *
* Under rare situations, incorrect intermediate calculations *
* can *
* lead to an inaccurate PCTPAGESSAVED value, including 0 and *
* *
* negative values. *
****************************************************************
* RECOMMENDATION: *
* Upgrade To DB2 Version 9.5 Fix Pack 7 *
**************************************************************** |
| Local Fix: |
Determine compression benefit from other compression statistics
PCTROWSCOMPRESSED and AVGROWCOMPRESSIONRATIO.
If PCTPAGESSAVED is 0 after an index-only RUNSTATS operation,
collect statistics again, ensuring to collect statistics for the
table as well as its indexes, for example:
RUNSTATS ON TABLE s.t AND INDEXES ALL |
| available fix packs: |
DB2 Version 9.5 Fix Pack 7 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 8 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 9 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 10 for Linux, UNIX, and Windows
|
| Solution |
First Fixed In DB2 Version 9.5 Fix Pack 7 |
| Workaround |
not known / see Local fix |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 12.02.2010
20.01.2011
20.01.2011 |
| Problem solved at the following versions (IBM BugInfos) |
9.5.FP7
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 9.1.0.7
|
 |
| 9.5.0.7
|
|
