PK71816: DSN1COMP ENHANCEMENT.

Obtain the fix for this APAR.

APAR status

• Closed as new function.

Error description

• DSN1COMP enhancement.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All DB2 for z/OS V8 and DB2 9 for z/OS       *
  *                 utility users of DSN1COMP.                   *
  ****************************************************************
  * PROBLEM DESCRIPTION: This APAR provides functionality to     *
  *                      externalize a compression dictionary    *
  *                      created in DSN1COMP as an object module *
  *                      . In the follow-on processing this      *
  *                      text-deck can be used to generate a     *
  *                      unique EDITPROC which allows            *
  *                      compression for encrypted data in DB2.  *
  ****************************************************************
  * RECOMMENDATION: Apply PTF when available.                    *
  ****************************************************************
  From DB2-users there is an increasing demand for being able to
  take advantage of the compression facilities of DB2 also for
  encrypted data.
  Up to now this is a restriction within DB2.
  

Problem conclusion

Temporary fix

Comments

• DSN1COMP has been changed so that the compression dictionary
  that is created in DSN1COMP for determining the compression
  report can be externalized and stored in a data set for further
  processing.
  
  The object module with the CSECT-name specified in option
  EXTNDICT is written to the data set identified with
  the DSN1DICT DD statement. It can be up to 64 KB. This
  externalized compresssion dictionary can be included into a
  program via the linkage editor. See the introductory
  information and information about dictionary formats in
  Enterprise Systems Architecture/390 Data Compression, SA22-7208,
  and the CMPSC information in
  z/Architecture Principles of Operation, SA22-7832.
  
  This enhancement requires changes to the external interface of
  DSN1COMP:
  
  1. A new option EXTNDICT has been added for DSN1COMP.
     EXTNDICT specifies the 8 character name of the
     link edittable object deck built from the DSN1COMP-created
     compression dictionary.
     The name has to follow the z/OS naming conventions. Only
     alpha-numeric characters (in upper-case) are allowed to
     build-up the name, the first character has to be non-numeric.
     The new keyword can be placed anywhere in the parameter list.
  
  2. Specifying option EXTNDICT requires to also provide a
     DSN1DICT DD statement in the DSN1COMP Job.
  
     DSN1DICT defines the output data set to which the generated
     object module is written and stored for follow-on processing.
     This data set has to be sequential or a member of a
     partitioned data set with the record-format fixed and a
     record-length of 80.
  
  An additional sample will be provided for the enhanced
  functionality of DSN1COMP:
  
  Example 4: Building an Object Module from the DSN1COMP generated
  dictionary.
  In the sample statement BUILD
  specifies that DSN1COMP is to externalize the DSN1COMP-generated
  compression dictionary. This is achieved by specifying option
  EXTNDICT which in addition requires that a DSN1DICT DD statement
  is provided. DSN1DICT identifies the output data set to
  which the generated object module is written and stored for
  follow-on processing.
  
  //BUILD    EXEC PGM=DSN1COMP,
  // PARM='DSSIZE(4G),EXTNDICT(dictname),ROWLIMIT(99999)'
  //SYSPRINT DD  SYSOUT=A
  //SYSUT1   DD DSN=DSNCAT.DSNDBD.DBIA2401.TPIA2401.I0001.A254,
  //            DISP=SHR
  //DSN1DICT DD DSN=&&OBJ,
  //         DISP=(,PASS),
  //         UNIT=SYSALLDA,SPACE=(TRK,(8,4)),
  //         DCB=(LRECL=80,BLKSIZE=4000,RECFM=FB)
  
  Two new messages have been added to DB2:
  
  DSN1937I csect-name TXT-DECK extndict BUILT  nn RECORDS WRITTEN
  Explanation:
  A text-deck has been generated from the dictionary and written
  to the data set specified with the DSN1DICT DD statement.
  The name of the text-deck is matching the value specified for
  EXTNDICT. The number of records written is provided in the
  message.
  Severity: 0 (informational)
  User Response: no action is required.
  
  DSN1938I csect-name ERROR WITH DSN1DICT DD STATEMENT OR WITH
  RELATED DATA SET.
  Explanation:
  An error was encountered when trying to write to the data set
  specified with the DSN1DICT DD statement.
  Severity: 8 (error)
  System Action: Processing terminates.
  User Response:
  Verify that a DSN1DICT DD statement has been defined and that
  the related data set is defined properly.
  Correct the cause of the problem and resubmit the job.
  

APAR Information

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

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

  UK41354 UK41355

Modules/Macros

• DSNIENSR DSN1COMP DSN1DCTE
  

Fix information

• Fixed component name

  DB2 OS/390 & Z/

• Fixed component ID

  5740XYR00

Applicable component levels

• R810 PSY UK41354

     UP08/11/20 P F811

• R910 PSY UK41355

     UP08/11/20 P F811

Fix is available

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