IT39149: SELECT WITH PDQ AND SUBQUERY CAN PRODUCE WRONG RESULTS

APAR status

• Closed as program error.

Error description

• With PDQ this example query is producing a different result then
  without using PDQ shows different results
  export PDQPRIORITY=10
  
  14.10.FC6 $ six dbaccess sysmaster -
  
  Database selected.
  
  > SELECT /*+ explain */ count(*)
  FROM systables t50, syscolumns t71
  WHERE t50.tabid = t71.tabid
  AND t71.tabid||';'||t71.colno in
  (SELECT tabid||';'||min(colno)
  FROM syscolumns group by tabid);> > > > >
  
  
        (count(*))
  
               104
  
  1 row(s) retrieved.
  =================================
  export PDQPRIORITY=0
  
  14.10.FC6 $ six dbaccess sysmaster -
  
  Database selected.
  
  > SELECT /*+ explain */ count(*)
  FROM systables t50, syscolumns t71
  WHERE t50.tabid = t71.tabid
  AND t71.tabid||';'||t71.colno in
  (SELECT tabid||';'||min(colno)
  FROM syscolumns group by tabid);> > > > >
  
  
        (count(*))
  
               265
  
  1 row(s) retrieved.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * Users of Informix Server prior to 12.10.xC16 and 14.10.xC8.  *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See Error Description                                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Upgrade to Informix Server 12.10.xC16 or 14.10.xC8.          *
  ****************************************************************
  

Problem conclusion

• Fixed in Informix Server 12.10.xC16 and 14.10.xC8.
  

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:

Fix information

• Fixed component name

  INFORMIX SERVER

• Fixed component ID

  5725A3900

Applicable component levels