IZ40921: INTERNAL ERROR SQL0901 FROM AN INCORRECT CORRELATION CAUSED BY A N OPTIMIZATION OF SCALAR SUBQUERY

DB2 Version 9.5 Fix Pack 4  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

• An incorrect correlation may be formed when DB2 is trying to
  rewrite scalar subquery to a more efficient access form. Users
  may see the message
  SQL0901N  The SQL statement failed because of a non-severe
  system error.
  Subsequent SQL statements can be processed.  (Reason "Bad
  Plan; Unresolved QNC
  found".)  SQLSTATE=58004
  Note that this error message may be caused by other problems.
  It is not necessary that it is caused by this problem. If the
  SQL statement does not contain any scalar subquery, it does
  not hit this problem. If the scalar subquery does not refer to
  columns outside of the subquery boundary, it also does not hit
  this problem.
  

Local fix

• Reduce the optimization level to 0 or 1 will avoid this problem.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * ALL                                                          *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * An incorrect correlation may be formed when DB2 is trying to *
  *    rewrite scalar subquery that references a column outside  *
  * the    subquery boundary                                     *
  *           to a more efficient access form. Users may see the *
  * message                                                      *
  * SQL0901N  The SQL statement failed because of a non-severe   *
  *    system error.                                             *
  *       Subsequent SQL statements can be processed.  (Reason   *
  * "Bad       Plan; Unresolved QNC                              *
  *               found".)  SQLSTATE=58004                       *
  *                  Note that this error message may be caused  *
  * by other problems.   It is not necessary that it is caused   *
  * by this problem. If the   SQL statement does not contain any *
  * scalar subquery, it does     not hit this problem. If the    *
  * scalar subquery does not refer to  columns outside of the    *
  * subquery boundary, it also does not hit  this problem.       *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Upgrade to DB2 Version 9.1 Fix Pack 7                        *
  ****************************************************************
  

Problem conclusion

• Fixed in DB2 Version 9.1 Fix Pack 7
  

Temporary fix

Comments

APAR Information

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

  IZ37337

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

Fix information

• Fixed component name

  DB2 POFE

• Fixed component ID

  5724N7700

Applicable component levels

• R910 PSN

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