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Problem IC91788
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Status: Closed |
IN2JOIN OPTIMIZATION GUIDELINE IS NOT APPLIED TO REWRITE IN PREDICATE TO A JOIN |
| product: |
DB2 FOR LUW / DB2FORLUW / A10 - DB2 |
| Problem description: |
In certain conditions, DB2 does not apply the IN-LIST-to-join
query
rewrite when the optimization guideline IN2JOIN is specified.
For example:
In the SQL statement below
SELECT ...
FROM PARTS P, SUPPLIERS S, PARTSUPP PS
WHERE P.PARTKEY = PS.PS_PARTKEY
AND S.S_SUPPKEY = PS.PS_SUPPKEY
AND P_SIZE IN (?, ?, ?, ...)
AND ...
and an optimization guideline
<OPTGUIDELINES><INLIST2JOIN TABLE='P'
COLUMN='P_SIZE'/></OPTGUIDELINES>
is specified. The statistics information of the table P and the
columns in the table are not sufficient to indicate that the
IN-LIST-to-join will outperform other optimization techniques.
However, when the optimization guideline IN2JOIN is specified,
DB2 should apply the optimization regardless of the outcome from
the analysis of the statistics information. |
| Problem Summary: |
****************************************************************
* USERS AFFECTED: *
* ALL *
****************************************************************
* PROBLEM DESCRIPTION: *
* See Error Description *
****************************************************************
* RECOMMENDATION: *
* Upgrade to DB2 V10.1 FP3 *
**************************************************************** |
| Local Fix: |
|
| available fix packs: |
DB2 Version 10.1 Fix Pack 3 for Linux, UNIX, and Windows
DB2 Version 10.1 Fix Pack 4 for Linux, UNIX, and Windows
DB2 Version 10.1 Fix Pack 3a for Linux, UNIX, and Windows
DB2 Version 10.1 Fix Pack 6 for Linux, UNIX, and Windows
|
| Solution |
Fixed in DB2 V10.1 FP3 |
| Workaround |
not known / see Local fix |
| Timestamps |
Date - problem reported :
Date - problem closed :
Date - last modified :
| 22.04.2013
09.12.2013
09.12.2013 |
| Problem solved at the following versions (IBM BugInfos) |
|
| Problem solved according to the fixlist(s) of the following version(s) |
| 10.1.0.3
|
 |
| 10.1.0.3
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