IT28641: SUBSTR IN COLUMN ORGANIZED COLUMN COMPARISON RETURN WRONG RESULTS

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

• Comparing a column from a column-organized table with an
  expression including the SUBSTR function may return wrong
  results, e.g.:
  
  db2 "insert into T(c1) values('201803')"
  db2 "select C1 from T where substr(C1,1,6) =
  substr('2018-03',1,4)|| substr('2018-03',6,2)"
  
  The problem occurs when the column is defined with string length
  unit CODEUNITS32 and the SUBSTR expression has constant
  arguments.
  

Local fix

• Replace the constant SUBSTR expression with a constant, e.g.
  replace SUBSTR('2018-03',1,4) with '2018' and replace
  SUBSTR('2018-03',6,2) with '03'.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * ALL                                                          *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See Error Description                                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Upgrade to Db2 version 11.1.4.6                              *
  ****************************************************************
  

Problem conclusion

• First fixed in Db2 version 11.1.4.6
  

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:

  IT35058

Fix information

• Fixed component name

  DB2 FOR LUW

• Fixed component ID

  DB2FORLUW

Applicable component levels

• RA10 PSN

     UP