|
Problem IT04002
|
Status: Closed |
QUERY PERFORMANCE DEGRADATION MAY OCCUR DUE TO A BAD FILTER FACTOR WHEN ORACLE COMPATIBILITY MODE IS ON. |
| product: |
DB2 FOR LUW / DB2FORLUW / 970 - DB2 |
| Problem description: |
When Oracle Compatibility Mode (VARCHAR2 mode) is on, one of
index scan may end up with a wrong filter factor(0.4), which
will lead to bad performance.
You may see the following plan under IXSCAN, which shows 0.4
filter factor, when the actual filter factor is less.
10) Start Key Predicate,
Comparison Operator: Equal
(=)
Subquery Input Required: No
Filter Factor: 0.04
Predicate Text:
--------------
(Q33.C1 = ORA_VARCHAR(:L33)) |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* ALL *
****************************************************************
* PROBLEM DESCRIPTION: *
* See Error Description *
****************************************************************
* RECOMMENDATION: *
* Upgrade to DB2 9.7 Fix Pack 11 *
**************************************************************** |
| Local Fix: |
|
| Solution |
First fixed in DB2 9.7 Fix Pack 11 |
| Workaround |
not known / see Local fix |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 25.08.2014
03.05.2017
03.05.2017 |
| Problem solved at the following versions (IBM BugInfos) |
9.7.FP11
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 9.7.0.11
|
 |
