DB2 FOR LUW / DB2FORLUW / 970 - DB2

A performance regression has been noticed. 
The access plan has the following characteristics: 
 
            NLJOIN 
                  | 
   +---------+---------+ 
 <ANY>             GRPBY 
                                 | 
                          TBSCAN 
 
 
1. There is an Nested Loop Join on at least two tables. 
2. The inner table of the Nested Loop join is a Group By 
operator 
3. No eligible index(es) on the inner table. 
4. Local predicate(s) applied on the inner table 
5. Fetch First N Rows is specified above the join. 
Inner table refers to the table used as the inner leg of a join 
in the access plan generated by the Optimizer 
 
Example: 
select * from T1, (select x from T2 where y = 'NAME' group by x) 
where T1.x = T2.x order by T2.x fetch first 200 rows 
 
Recommended Workaround: 
1. create index ix1 on T2(x) 
2. RUNSTATS ON TABLE <schema>.T2 FOR INDEXES ALL

USERS AFFECTED: All 
 
PROBLEM DESCRIPTION: 
 
see ERROR DESCRIPTION 
 
PROBLEM SUMMARY: 
 
see ERROR DESCRIPTION

Create qualified indexes on the all join columns of the inner 
table and perform runstats.

DB2 Version 9.7 Fix Pack 2 for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 3 for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 3a for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 4 for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 5 for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 6 for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 7 for Linux, UNIX, and Windows
 DB2 Version 9.7 Fix Pack 9a 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 10 for Linux, UNIX, and Windows
 

The complete fix for this problem first appears in DB2 UDB 
Version 9.7 FixPak 2.

keiner bekannt / siehe Local-Fix

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

26.10.2009
18.05.2010
18.05.2010

9.7.