PRELOAD

Specifying the default

You can specify the default for the PRELOAD command option in your installation options module by using the PRELOAD installation option. However, you can specify only CONTINUE or LOAD for the installation option. LOADPLUS was shipped with a default value of LOAD for this option. Any PRELOAD command option that you specify overrides the default that is in the installation options module.

LOAD

If you specify PRELOAD LOAD, LOADPLUS uses single-phase load processing, which combines the functions of the PRELOAD and LOAD phases into the COMBINED phase. LOADPLUS reads the input data and copies it directly to the table space. This phase can improve performance in most cases. See Performance-considerations-for-the-PRELOAD-LOAD-installation-and-command-options for details.

Restriction

When invoking DSNUTILB, LOADPLUS ignores this option.

CONTINUE

PRELOAD CONTINUE tells LOADPLUS to use two-phase processing and to continue with the LOAD phase after the PRELOAD phase is completed.

Restrictions

The following restrictions apply to PRELOAD CONTINUE:

• If you are loading LOB or XML data, LOADPLUS invokes DSNUTILB.
• If you also specify ENFORCE RI or ENFORCE CONSTRAINTS, LOADPLUS terminates. If you want LOADPLUS to check referential constraints during the load job, specify PRELOAD LOAD.
• LOADPLUS ignores this option when either of the following conditions exists:
  • LOADPLUS is invoking DSNUTILB.
  • You are running an SQLAPPLY load.

ANALYZE

The PRELOAD ANALYZE option tells LOADPLUS to use two-phase processing, but to stop after the optimization phase of the PRELOAD phase. No data is read and no tables are affected. LOADPLUS displays message BMC51496I indicating the optimal number of sort tasks, read tasks, and index tasks. You can use this information to adjust the number of data sets that you specify in your JCL before resubmitting your job.

Restrictions

LOADPLUS terminates when any of the following conditions exists and you specify PRELOAD ANALYZE:

• You are loading LOB or XML data.
• You are running an SQLAPPLY load.
• LOADPLUS is invoking DSNUTILB.

• You also specify ENFORCE RI or ENFORCE CONSTRAINTS.

  If you want LOADPLUS to check referential constraints during the load job, specify PRELOAD LOAD.

PAUSE

The PRELOAD PAUSE option tells LOADPLUS to use two-phase processing, but to pause after the PRELOAD phase.

This option is particularly useful if you want to control your outage when running LOAD REPLACE with SHRLEVEL NONE. For this type of load, LOADPLUS normally stops the table space during the LOAD phase instead of the PRELOAD phase. By specifying PRELOAD PAUSE, you can schedule the LOAD phase to minimize the impact on data availability.

Restarting

You can restart the utility at the beginning of the LOAD phase by specifying RESTART or RESTART(PHASE) on your EXEC statement. Note the following information about restarting your PRELOAD PAUSE job:

• You do not need to change the PRELOAD option on the LOAD command. When restarting a PRELOAD PAUSE job, LOADPLUS ignores the PAUSE specification.
• If you also specify LOAD RESUME YES and SHRLEVEL NONE is in effect, the participating objects must remain in stopped status before you restart your job.

Restrictions

LOADPLUS terminates when any of the following conditions exists and you specify PRELOAD PAUSE:

• You are loading LOB or XML data.
• You are running an SQLAPPLY load.
• LOADPLUS is invoking DSNUTILB.

• You also specify ENFORCE RI or ENFORCE CONSTRAINTS.

  If you want LOADPLUS to check referential constraints during the load job, specify PRELOAD LOAD.