IT19659: DB2 MIGHT ABEND WHEN EXECUTING QUERIES WITH MULTIPLE OUTER JOINSAND EQUALITY PREDICATES

Db2 Version 11.1 Mod 4 Fix Pack 6 for Linux, UNIX, and Windows
Db2 Version 11.1 Mod 4 Fix Pack 6 for Linux, UNIX, and Windows

APAR status

• Closed as program error.

Error description

• Under rare cases, DB2 might abend when the following conditions
  are true:
  1) The query contains 3 or more left outer joins
  2) The Join predicate in the top-most left join references a
  column from the null-producing side of the lowest left join.
  3) The same column is also referenced in an equality predicate
  in an inner join
  
  e.g.: Select *
      from t1 left join t2 on t1.c1 = t2.c1
              left join t3 on t1.c1 = t3.c1
              inner join t4 on t2.c1 = t4.c1
              left join t5 on t2.c1 = t5.c1
  

Local fix

• db2set -im DB2COMPOPT=NOOJSJ
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * ALL                                                          *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See Error Description                                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Upgrade to Db2 Version 11.1 Mod 4 FixPack 6.                 *
  ****************************************************************
  

Problem conclusion

• First fixed in Db2 Version 11.1 Mod 4 FixPack 6.
  

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

  DB2 FOR LUW

• Fixed component ID

  DB2FORLUW

Applicable component levels

• RB10 PSN

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