DB2 FOR LUW / DB2FORLUW / 950 - DB2

MQT creation might trap with infinite recursive calls of 
sqlnq_reroutable_ast_rec in the trap file. This happens only 
when MQT definition has the following characteristics: 
1. MQT definition has CSE (Common Sub Expression), called V1 
2. MQT has recursive UNION ALL construct, called V2. V2 has two 
union all branches. The first union branch references V1 and the 
second branch references V1 and V2 of course. 
3. V2 second branch has IN predicate and the element list 
consists of multiple values or expressions. 
 
Example: 
-- create a base table 
create table t1(c1 int, c2 int); 
-- mqt creation traps 
create table mqt as ( 
with v1(c1, c2) as (select * from t1), 
      v2(level, c1, c2) as (select 1, v1.* from v1 union all 
                                  select parent.level+1, 
parent.c1, parent.c2 from v2 parent, v1 child 
                                  where parent.c1 = child.c1 and 
child.c2 in (1,2) and parent.level < 10) 
select c1, c2 from v2 
) data initially deferred refresh deferred;

**************************************************************** 
* USERS AFFECTED:                                              * 
* All                                                          * 
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* PROBLEM DESCRIPTION:                                         * 
* See Problem Description above.                               * 
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* RECOMMENDATION:                                              * 
* Upgrade to DB2 Version 9.5 Fix Pack 9.                       * 
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Make V1 a regular view and change MQT definition to reference V1 
instead of common table expression.

DB2 Version 9.5 Fix Pack 9 for Linux, UNIX, and Windows
 DB2 Version 9.5 Fix Pack 10 for Linux, UNIX, and Windows
 

First fixed in DB2 Version 9.5 Fix Pack 9.

not known / see Local fix

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

26.08.2011
14.03.2012
14.03.2012

9.5.FP9