Fixes are available
DB2 Version 9.5 Fix Pack 3b for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 1 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 2a for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 2 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 4 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 3a for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 3 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 4a for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 5 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 6a for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 7 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 8 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 9 for Linux, UNIX, and Windows
DB2 Version 9.5 Fix Pack 10 for Linux, UNIX, and Windows
APAR status
Closed as program error.
Error description
Due to changes in the DB2 optimizer code that started in Fix Pack 10, a very complex query that used to work fine before the upgrade, it may return the following warning after the upgrade: SQL0437W Performance of this complex query may be sub-optimal. Reason code: "1". SQLSTATE=01602. Explanation: The statement may achieve sub-optimal performance since the complexity of the query requires resources that are not available or optimization boundary conditions were encountered. The following is a list of reason codes: 1 The join enumeration method was altered due to memory constraints. 437rc1 is about switching dynamic programming join enumeration to greedy join enumeration.
Local fix
db2set db2_reduced_optimization=yes Alleviate the switch by reducing memory consumption. or Reduce the current query optimization level (e.g. set current query optimization 2) Avoid the switch as opt level 2 uses greedy vs opt level 5 uses dynamic.
Problem summary
see problem description
Problem conclusion
First fixed in DB2 UDB Version 9.5, FixPak 1
Temporary fix
Comments
APAR Information
APAR number
IZ09197
Reported component name
DB2 UDB ESE SOL
Reported component ID
5765F4102
Reported release
950
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2007-11-21
Closed date
2008-05-05
Last modified date
2011-08-29
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Fix information
Fixed component name
DB2 UDB ESE SOL
Fixed component ID
5765F4102
Applicable component levels
R910 PSY
UP
R950 PSY
UP
Document Information
Modified date:
01 October 2021