The part of maintenance you control

Most of the persistent data store maintenance procedure is automatic and does not require your attention. However, there are a few options you must decide upon.

Important: The content in this section was created for and applies to the original persistent data store, referred to as PDS V1. A new PDS version (referred to as PDS V2) now exists. PDS V1 will eventually be deprecated.
In the PARMGEN configuration method, you use the following parameters to select the options of BACKUP, EXPORT, and EXTRACT:
  • RTE_PDS_BACKUP_FLAG
  • RTE_PDS_EXPORT_FLAG
  • RTE_PDS_EXTRACT_FLAG
By default, these are all set to N. You can also set the parameter RTE_PDS_BATCHINT_FLAG, which has a default of N. If the BACKUP, EXPORT, EXTRACT, and BATCHINT flags are set to N, then the data set is re-initialized within the address space without reallocating the data set. If any of these flags is set to Y, then the Persistent Datastore maintenance procedure is run to empty a data set. See Command interface for descriptions of additional commands that are used primarily for maintenance.
  • BACKUP makes an exact copy of the data set being maintained.
    You can indicate one of these backup options:
    • Back up the data for each data set group.
    • Back up the data to tape or to DASD for all data set groups.
  • EXPORT writes the data to a flat file in an internal format that can be used by external programs to post process the data. This file is also used for recovery purposes when the persistent data store detects potential problems with the data.
  • EXTRACT writes the data to a flat file in human-readable form, which is suitable for loading into other DBMS systems. The EXTRACT option is not strictly considered a way to maintain the data. If EXTRACT is specified, the data is pulled out and externalized in EBCDIC form, but the extraction does not empty the data set. If EXTRACT is specified, the data is extracted immediately from a data set that is switched from an active state to a full state. The data set is not initialized until it becomes a candidate for being emptied, so the most current data becomes available in an extracted form without that data being lost.
If none of the options is specified, the data in the data set being maintained is erased.

For more information about configuring maintenance, see Allocate data sets and configure maintenance for historical data.