home clear 64x64
en blue 200x116 de orange 200x116 info letter User
suche 36x36
Latest versionsfixlist
11.1.0.7 FixList
10.5.0.9 FixList
10.1.0.6 FixList
9.8.0.5 FixList
9.7.0.11 FixList
9.5.0.10 FixList
9.1.0.12 FixList
Have problems? - contact us.
Register for free anmeldung-x26
Contact form kontakt-x26

DB2 - Problem description

Problem IT02568 Status: Closed

DB2 MIGHT PRODUCE A SQL0901N WHEN PLANNING EARLY OUT NESTED LOOP JOIN

product:
DB2 FOR LUW / DB2FORLUW / A50 - DB2
Problem description:
Under rare scenarios, DB2 might produce SQL0901N if the 
following conditions are true: 
1) The query block has a group by with one or more aggregation 
functions of the form MAX, MIN and SUM. 
2) One or more columns referenced in the aggregate functions are 
also used in a predicate in the null value rejecting context. 
3) The same columns are also referenced in a correlated subquery 
containing two or more tables 
4) There is an index on a subset of these columns. 
5) The access plan for the query shows a early out nested loop 
join where the subquery is applied in the INNER scan as residual 
predicate 
 
Sample query: 
SELECT * 
FROM  T1, 
               (SELECT Max(c2)   c2_max 
                FROM   (SELECT t2.c1, t2.c2 
                            FROM    t2, 
                                        t3 
                            WHERE  t3.c3 = t2.c3 
                               AND t2.c3 = ? 
                               AND t2.c2 = t3.c2 
                               AND NOT EXISTS (SELECT 1 
                                                          FROM 
 
t2 as t4, t5 
                                                          WHERE 
 
t4.c3 = t5.c3 AND t2.c2 < t4.c3)) 
                            GROUP  BY c1) tmp 
WHERE  t1.c2 = tmp.c2_max; 
 
Error message: 
SQL0901N  The SQL statement or command failed because of a 
database system error. (Reason "got a cond_isnotnull after 
building outer".)  SQLSTATE=58004
Problem Summary:
**************************************************************** 
* USERS AFFECTED:                                              * 
* Users running DB2 10.1 before Fix Pack 5                     * 
**************************************************************** 
* PROBLEM DESCRIPTION:                                         * 
* See Error Description                                        * 
**************************************************************** 
* RECOMMENDATION:                                              * 
* Upgrade to DB2 10.1 Fix Pack 5 or later                      * 
****************************************************************
Local Fix:
db2set DB2_REDUCED_OPTIMIZATION=NO_NLJN_EO_FOR_GB
Solution
Workaround
not known / see Local fix
Timestamps
Date  - problem reported    :
Date  - problem closed      :
Date  - last modified       :
13.06.2014
31.03.2015
31.03.2015
Problem solved at the following versions (IBM BugInfos)
Problem solved according to the fixlist(s) of the following version(s)
10.5.0.5 FixList