Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• SQL RELATED PERFORMANCE DEGRADATION IN DB2 V8 ENFM AND CM MODE,
  DB2 for z/OS V8 compatibility mode users should also apply DB2
  APAR PK12398.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All DB2 V8 Compatibility Mode and Enable New *
  *                 Function Mode users                          *
  ****************************************************************
  * PROBLEM DESCRIPTION: Poor query performance may occur when   *
  *                      there are data type and/or length       *
  *                      mismatches in predicates on V8 CM or    *
  *                      V8 ENFM.                                *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  Users in New Function Mode will not be impacted.
  
  PK12389 moves a major SQL optimization enhancement from new
  function mode to compatibility mode and Enable New Function
  Mode.  The enhancement which provides DB2 the ability to use
  indexes when there are data type and length mismatches will now
  be available within compatibility mode and enable new function
  mode.  Prior to this APAR, only new function mode systems had
  this enhancement available.
  
  For a more detailed description of this enhancement, see:
  Title:   DB2 UDB for z/OS V8 What's New?
  Document number: GC18-7428-00
  Chapter:    2.4.3 Ability to use an index in more situations
  

Problem conclusion

• Code was changed in DB2 to use indexes when there are data type
  and length mismatches within compatibility mode and enable new
  function mode.
  
  ADDITIONAL KEYWORDS: SQLPERFORMANCE SQLNLJ SQLTYPEMISMATCH
                       SQLCOMPATMODE
  

Temporary fix

• *********
  * HIPER *
  *********
  

Comments

APAR Information

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

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

  UK10002

Modules/Macros

• DSNXOCAT
  

Fix information

• Fixed component name

  5740 IBM DATABA

• Fixed component ID

  5740XYR00

Applicable component levels

• R810 PSY UK10002

     UP06/03/11 P F603

Fix is available

• Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.

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Product categories:

Software

Data Management

Data Servers (Database Management Systems)

DB2 for z/OS

Software version:

810

Reference #:

PK12389

IBM Group:

Software Group

Modified date:

2006-05-08