DB2 FOR LUW / DB2FORLUW / 970 - DB2

The performance of an XQUERY which contains path extraction in a 
'for loop' statement, such as 'for ... let' and 'for ...', 
has a bad performance in V97 compared to V91.  While the 
performance is bad in general, some queries may show worse 
performance than the others, depending on the amount of data to 
be extracted. The problem is caused by a bad plan being chosen 
by the optimizer. 
 
An example of such query is: 
----- 
xquery declare namespace xxxx="http://xxxx"; let $base := 
db2-fn:xmlcolumn("xxxx")/ap:LimitData for $name in 
fn:distinct-values( $base[./xxxx:ScheduleDate < 
xs:string(fn:current-date())]/xxxx:ChargeList/xxxx:Charge/xxxx:U 
serSectionName ), $count in fn:count( $base[./xxxx:ScheduleDate 
< xs:string(fn:current-date()) and 
./xxxx:ChargeList/xxxx:Charge/xxxx:UserSectionName=$name] ) 
order by $name return <xxxx:LDOutline> <xxxx:Name>{ $name 
}</xxxx:Name> <xxxx:Count>{ $count } </xxxx:Count> 
</xxxx:LDOutline>@ 
----- 
 
Another example of such query is : 
----- 
xquery declare namespace xxxx="http://xxxx"; let $base := 
db2-fn:xmlcolumn("xxxx")/xxxx:LimitData for $name in 
fn:distinct-values( $base[./xxxx:ScheduleDate < 
xs:string(fn:current-date())]/xxxx:ChargeList/xxxx:Charge/xxxx:U 
serSectionName ) 
order by $name return <xxxx:LDOutline> <xxxx:Name>{ $name } 
</xxxx:Name> <xxxx:Count> { fn:count( $base[./xxxx:ScheduleDate 
< xs:string(fn:current-date()) and ./xxxx:ChargeList/xxxx: 
Charge/xxxx:UserSectionName=$name] ) } 
</xxxx:Count> </xxxx:LDOutline> ; 
-----

**************************************************************** 
* USERS AFFECTED:                                              * 
* DB2 UDB Version 9.7.                                         * 
**************************************************************** 
* PROBLEM DESCRIPTION:                                         * 
* See Error description field for more information.            * 
**************************************************************** 
* RECOMMENDATION:                                              * 
* Upgrade to Version 9.7 FixPack 6.                            * 
****************************************************************

DB2 Version 9.7 Fix Pack 7 for Linux, UNIX, and Windows
 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
 

Problem was first fixed in DB2 UDB Version 9.7 FixPack 6. 
Upgrade to Version 9.7 FixPack 6.

not known / see Local fix

forerunner  : APAR is sysrouted TO one or more of the following: IC80587 
follow-up : 

Date  - problem reported    :
Date  - problem closed      :
Date  - last modified       :

21.12.2011
20.10.2012
20.10.2012

9.7.FP6