The damadd command adds a logical file to an online system. This addition processing defines an existing physical file as a logical file. The user must create a physical file before executing the damadd command.

The deferred update facility can be used by specifying the -d option in the damadd command. Specifying this option makes it possible to add specified logical files as files subject to deferred updating.

The -n option of the damadd command enables a DAM file to be additionally registered as a file not to be recovered. If you wish to specify cacheless access for the file, also specify the -f option.

The damrm command removes a logical file from the online system, and the damdel command deletes a physical file. To delete a physical file being used in the online mode, the user must remove the corresponding logical file from the online system with the damrm command before executing the damdel command.

A DAM file used in the online mode (opened) cannot be removed from the online system by the damrm command. To remove the DAM file from the online system, the appropriate logical file must be closed in all services under which it is opened.