DB2 FOR LUW / DB2FORLUW / A10 - DB2

XQuery might return incorrect result when both 'AND' and 'OR' 
predicates exist, and all predicate can be applied to XML 
indexes. 
 
The following example shows a sample XQuery: 
----- a.sql ---------------------- 
select count(*) from xxxxx.xxxxxxx 
where xmlexists(' 
declare namespace xxxx = "xxxxxxxxx"; 
$data/ap:User 
  [ap:sex = "male"] 
  [ap:address = "tokyo"] 
  [ap:status = "10" or ap:status = "40"] 
' passing data as "data") 
@ 
---------------------------------- 
 
In this example, there are no explicit AND 
predicates. However, the three filters in the XQuery statement 
get combined 
to be: 
[ap:sex = "male" and ap:address = "tokyo" and  (ap:status = "10" 
or ap:status = "40")] 
The DB2 database might incorrectly 
decide that navigation is not needed and might lead to incorrect 
results when the following conditions are satisfied: 
 
- There are both AND and OR terms in the XQuery 
- All subterms are applicable to XML indexes 
- There is no extraction of data from the XML document, for 
example using XMLEXISTS 
 
The problem can affect both, SQL/XML and XQuery statements. 
SQL/XML statements that are simple and do not apply 
predicates to XML indexes are not affected by this problem.

**************************************************************** 
* USERS AFFECTED:                                              * 
* All users                                                    * 
**************************************************************** 
* PROBLEM DESCRIPTION:                                         * 
* See Error Description                                        * 
**************************************************************** 
* RECOMMENDATION:                                              * 
* Upgrade to DB2 version 10.1.0.2.                             * 
****************************************************************

Adding an 'or fn:false()' term to the OR predicates will prevent 
this from occuring. 
. 
Here is an example work around for the above: 
----- a.sql ---------------------- 
select count(*) from xxxxx.xxxxxxx 
where xmlexists(' 
declare namespace xxxx = "xxxxxxxxx"; 
$data/ap:User 
  [ap:sex = "male"] 
  [ap:address = "tokyo"] 
  [ap:status = "10" or ap:status = "40" or fn:false()] 
' passing data as "data") 
 
@ 
----------------------------------

DB2 Version 10.1 Fix Pack 2 for Linux, UNIX, and Windows
 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
 

The problem is first fixed in DB2 version 10.1.0.2.

keiner bekannt / siehe Local-Fix

Datum - Problem gemeldet    :
Datum - Problem geschlossen :
Datum - der letzten Änderung:

30.07.2012
07.12.2012
07.12.2012