LI72983: REPARTITION JOIN STRATEGY NOT CONSIDERED IN DPF ENVIRONMENT WHEN DB2_REDUCED_OPTIMIZATION IS SET

DB2 Version 9.1 Fix Pack 7  for Linux, UNIX and Windows
DB2 Version 9.1 Fix Pack 5   for Linux, UNIX and Windows
DB2 Version 9.1 Fix Pack 6   for Linux, UNIX and Windows
DB2 Version 9.1 Fix Pack 6a for Linux, UNIX and Windows
DB2 Version 9.1 Fix Pack 7a  for Linux, UNIX and Windows
DB2 Version 9.1 Fix Pack 8  for Linux, UNIX and Windows
DB2 Version 9.1 Fix Pack 9  for Linux, UNIX and Windows
DB2 Version 9.1 Fix Pack 10  for Linux, UNIX and Windows
DB2 Version 9.1 Fix Pack 11  for Linux, UNIX and Windows
DB2 Version 9.1 Fix Pack 12  for Linux, UNIX and Windows

APAR status

• Closed as program error.

Error description

• Repartition join strategy is not considered in a DPF
  environment, when DB2_REDUCED_OPTIMIZATION is turned on. This
  limitation will be relaxed for OUTER JOINS with this fix.
  
  Without this fix, large tables or fact table on null producing
  side can be broadcasted to tuple preserving side, which leads to
  bad performance of the query.
  

Local fix

Problem summary

• Repartition join strategy is not considered in a DPF
  environment, when DB2_REDUCED_OPTIMIZATION is turned on. This
  limitation will be relaxed for OUTER JOINS with this fix.
  
  Without this fix, large tables or fact table on null producing
  side can be broadcasted to tuple preserving side, which leads to
  bad performance of the query.
  

Problem conclusion

• First fixed in DB2 UDB Version 9.1, FixPak 5
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  LI72999

Fix information

• Fixed component name

  DB2 UDE ESE LIN

• Fixed component ID

  5765F4104

Applicable component levels

• R810 PSN

     UP

• R820 PSN

     UP

• R910 PSN

     UP

• R950 PSN

     UP