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Defining, Generating, and Punching a DMCL › Procedure for Defining a DMCL

Procedure for Defining a DMCL

Steps for Defining the Central Version DMCL

To create a DMCL for use under the central version, follow these steps:

Action

Statement

Create the DMCL

CREATE DMCL

Create one or more database buffers

CREATE BUFFER

Create 1 journal buffer

CREATE JOURNAL BUFFER

Create 2 or more disk journal files

CREATE DISK JOURNAL

Create 1 or more archive journal files

CREATE ARCHIVE JOURNAL

Add all segments to be used under the central version or in local mode

ALTER DMCL with the ADD SEGMENT clause

Optionally, override file or area definitions contained in segments associated with the DMCL

ALTER DMCL with the ADD FILE or ADD AREA clauses

Associate a database name table with the DMCL

ALTER DMCL with the DBTABLE clause

Example

The following example creates a DMCL to be used under the central version and in local mode. The DMCL defines one large buffer. For applications run locally, the buffer contains 100 4096-byte pages. Under the central version, the buffer initially contains 500 pages; you can increase the number of pages to 1500 dynamically by issuing a DCMT VARY BUFFER command.

create dmcl proddmcl dbtable proddbs;

create buffer big_buffer
   page size 4096
   local mode buffer pages 100
      opsys storage
   central version mode buffer
      initial pages 500
      maximum pages 1500
      opsys storage;

create journal buffer jrnlbuff
   page size 4096
   buffer pages 3;

create disk journal diskjnl1
   file size 1000
   assign to sysjnl1;

create disk journal diskjnl2
   file size 1000
   assign to sysjnl2;

create disk journal diskjnl3
   file size 1000
   assign to sysjnl3;

create archive journal archjrnl
   block size 16000
   assign to sysajnl1;

alter dmcl proddmcl
   default buffer big_buffer
   add segment system
   add segment defdict
   add segment empdict
   ...
   add segment empseg;

Steps for Defining a Local Mode DMCL

To create a DMCL for local mode only, follow the same steps as in defining a DMCL for central version use, except define a tape journal file instead of disk and archive journal files.

create dmcl idmsdmcl dbtable proddbs;

create buffer locl_buffer
   page size 16000
   local mode buffer pages 100
      opsys storage;

create journal buffer jrnlbuff
   page size 4096
   buffer pages 3;

create tape journal tapejnl1
   assign to tapejrnl;

alter dmcl idmsdmcl
   default buffer locl_buffer
   add segment defdict
   add segment catdict
   add segment empdict
   ...
   add segment empseg;