SQL4023 - Parallel table prefetch used

SQL4023
Message Text: Parallel table prefetch used
Cause Text: The query optimizer chose to use a parallel prefetch access method to reduce the processing time required for the table scan.
Recovery Text: Parallel prefetch can improve the performance of queries. Even though the access plan was created to use parallel prefetch, the system will actually run the query only if the following are true:
  • The query attribute degree was specified with an option of *IO or *ANY for the application process.
  • There is enough main storage available to cache the data being retrieved by multiple I/O streams. Normally, 5 megabytes would be a minimum. Increasing the size of the shared pool may improve performance.
For more information about parallel table prefetch, refer to Data access on DB2 UDB for iSeries: data access paths and methods