Initializing an empty database

You can use the Initialize dialog to create a batch job that initializes your IMS database.

You can initialize these types of IMS databases:

  • HDAM - Hierarchical Direct Access Method
  • HIDAM - Hierarchical Index Direct Access Method
  • HISAM - Hierarchical Index Sequential Access Method
  • SHISAM - Simple Hierarchical Index Sequential Access Method
  • DEDB - Data Entry Database (Fast Path)
  • PHDAM - Partitioned Hierarchical Direct Access Method (HALDB)
  • PHIDAM - Partitioned Hierarchical Index Direct Access Method (HALDB)

To generate the JCL for a job that initializes an IMS database:

  1. Select option 3 Utilities from the Primary Option Menu and then option 2 Initialize from the Utility Menu. The Initialize Entry Panel is displayed.
  2. In the Subsystem name field, enter the ID of the IMS subsystem that the database you want to initialize is defined in, or if you want to select the required subsystem from a list, enter a subsystem name pattern or leave the field blank.
  3. In the Database name field, enter the name of the database that you want to initialize, or if you want to select a database from a list of DBDs, enter a database name pattern or leave the field blank. When the database you specify is logically related to other databases, the Initialize also initializes the logically related databases.
  4. If you want the generated JCL to include a job step that uses GENJCL.IC commands to generate an image copy job:
    • Enter "/" in the Submit image copy field.
    • Enter in the Image Copy Skeleton field, the name of the partitioned data set that contains the image copy skeletons that you want the Initialize to use.

    The generated image copy job is submitted to the internal reader.

  5. If you selected a database that is not a HALDB and an IMS subsystem that is not a dynamic allocation only subsystem, in the Fetch DB dsnames from field:
    • Enter 1 if you want the function to initialize the database data sets whose names were saved in your user profile.
    • Enter 2 if you want the function to initialize the database data sets specified in the DFSMDA dynamic allocation members.
  6. If you want the generated JCL to include job steps that delete and redefine the database data sets, enter "/" in the Delete/Define DB data sets field.
  7. If you want to skip the display of the Database Data Set Specification or the Database Data Set Display panel, enter "/" in the Skip DB data set panel field.
  8. Press Enter to process the data you entered. According to what you entered on the panel, one or more of these panels may be displayed in the order they are listed:
    • Subsystem Selection panel
      • Displayed when you enter no subsystem name or a subsystem name pattern.
      • Displays a list of IMS subsystems defined by the FM/IMS administrator at installation time.
    • Database Selection panel
      • Displayed when you enter no database name or a database name pattern.
      • Displays a list of the DBDs in the DBD libraries for the specified subsystem.

      If the DBD libraries for the subsystem are not fixed, you specify the DBD libraries for the subsystem on the PSB and DBD Data Sets panel (option 0.6.7). If the DBD libraries for the subsystem are fixed, the FM/IMS administrator specifies the DBD libraries for the subsystem at installation time.

    On each selection panel that is displayed, enter an s in the Cmd field adjacent to the item you want to select and press Enter.

  9. If you did not select the Skip DB data set panel option, either the Database Data Set Display or the Database Data Set Specification panel is displayed.
    • The Database Data Set Display panel is displayed when a database that is a HALDB or a subsystem that is defined as dynamic allocation only is selected on the Initialize Entry panel. This panel displays the names of the database data sets that the function initializes. Verify that the database data sets listed are the ones you want the function to use. To confirm usage of these data sets and to proceed to the next panel in the dialog, press Enter.
    • The Database Data Set Specification panel is displayed when a database that is not a HALDB and a subsystem that is not defined as dynamic allocation only is selected on the Initialize Entry panel. If you selected "User profile" for the Fetch DB dsnames from option, it displays the data set names saved in your user profile. If you selected DFSMDA members for the Fetch DB dsnames from option, it displays the data set names specified in the DFSMDA dynamic allocation members for the subsystem.
      The Database Data Set Specification panel is displayed when the Skip DB data set panel option is not selected, but it is also displayed when the Skip DB data set panel option is selected and one of the following conditions is true:
      • FM/IMS fails to obtain all the required data set names from either your user profile or the DFSMDA members.
      • One or more of the database data sets does not exist or has an invalid data set organization.

      If the displayed data set names are not the ones you want the function to use or no data set names are displayed, enter the data set names that you want the function to use and press Enter. To confirm usage of the displayed data set names and to proceed to the next panel in the dialog, press Enter once more.

  10. FM/IMS retrieves the data set information and builds a job to initialize these data sets.

    The generated JCL contains instructions appropriate to the database type and selected options:

    • If you selected Delete/Define IMS data sets, the JCL also contains the instructions to delete/define these data sets.
    • For a DEDB Fast Path, the IMS Utility DBFUMIN0 is used to initialize the Fast Path areas.
    • For a Full Function database, the steps to initialize the database are:
      • Delete Work data sets. See Note a and b.
      • IMS Prereorganization Utility (DFSURPR0). See Notes a and b.
      • Database load.
      • IMS Database Prefix Resolution Utility (DFSURG10). See Notes a and b.
      • HISAM Reorganization Unload Utility (DFSURUL0). See Note a.
      • IMS HISAM Reorganization Load Utility (DFSURRL0). See Note a.
      • IMS Database Prefix Update Utility (DFSURGP0). See Note b.
      • Database segment delete.
      • Generate IMS image copy (DSPURX00). See Note c.
      • Delete Work data sets. See Notes a and b.
    • For a HALDB database, the steps to initialize the database are:
      • Delete Work data sets.
      • PINIT DBRC STEP (DSPURX00). Set the master HALDB database to PINIT, so all partitions need to be initialized.
      • IMS Prereorganization Utility (DFSURPR0). Use to initialize the HALDB partitions.
      • Generate IMS image copy (DSPURX00). See Note c.
      • Delete Work data sets.
    Note:
    1. This step only runs when the Database has secondary indexes
    2. This step only runs when the Database has logical relationships.
    3. The GENJCL step only runs if the Submit image copy flag has been selected for the database. Databases that use DBRC (particularly HALDBs) are unusable until an image copy has been run for the IMS database.

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