The DUMPSTAMP option enables the use of the incremental and accumulated dump feature in DMUTILITY. This option allocates a new word to store the last update timestamp of each data block. This option is valid for data sets, sets, and subsets. The DUMPSTAMP option is not allowed for partitioned data sets.

The incremental and accumulated dump feature in DMUTILITY uses the timestamp value to detect when data blocks have been modified. This information is then used to determine whether each data block is included in the incremental or accumulated dump.

When you choose to back up data sets, sets, and subsets using the incremental or accumulated dump feature, you must set the DUMPSTAMP option. You can set the default at the global database, data set, or set level or at the structure level in the physical options for data sets and their associated sets. Specifying DUMPSTAMP or DUMPSTAMP=TRUE sets the option. Setting DUMPSTAMP to TRUE for existing structures requires a file format reorganization, but no recompilation of application programs is necessary.

Once the DUMPSTAMP option is set, it remains set unless the CHECKSUM option is to reset. In this case, DUMPSTAMP is automatically reset by DASDL, and the incremental and accumulated dump capabilities are disabled. A file format reorganization is required when the DUMPSTAMP setting has been changed. INDEPENDENTTRANS and CHECKSUM must also be set when DUMPSTAMP is set to TRUE.

Provided that the CHECKSUM option is set, the DUMPSTAMP option is set by default under either of the following conditions:

Refer to the Enterprise Database Server Utilities Operations Guide for additional information about the incremental and accumulated dump feature.