Deleted records

 

The DLTPCT parameter specifies the percentage of deleted records that each physical file member can contain before you want the system to send a message to the system history log (CRTPF, CHGPF, CRTSRCPF, and CHGSRCPF commands).

When a file is closed, the system checks the member to determine the percentage of deleted records. If the percentage exceeds the value specified in the DLTPCT parameter, a message is sent to the history log. (For information about processing the history log, see the Control language topic collection. One reason you might want to know when a file reaches a certain percentage of deleted records is to reclaim the space used by the deleted records. After you receive the message about deleted records, you can run the Reorganize Physical File Member (RGZPFM) command to reclaim the space. You can also specify to bypass the deleted records check by using the *NONE value for the DLTPCT parameter. *NONE is the default for the DLTPCT parameter. REUSEDLT parameter specifies whether deleted record space should be reused on subsequent write operations (CRTPF and CHGPF commands). When you specify *YES for the REUSEDLT parameter, all insert requests on that file try to reuse deleted record space. Reusing deleted record space allows you to reclaim space used by deleted records without having to issue a RGZPFM command. When the CHGPF command is used to change a file to reuse deleted records, it might take a long time to run, especially if the file is large and there are already a lot of deleted records in it. It is important to note the following items:

• The term arrival order loses its meaning for a file that reuses deleted record space. Records are no longer always inserted at the end of the file when deleted record space is reused.

• If a new physical file is created with the reuse deleted record space attribute and the file is keyed, the FIFO or LIFO access path attribute cannot be specified for the physical file, nor can any keyed logical file with the FIFO or LIFO access path attribute be built over the physical file.

• You cannot change an existing physical file to reuse deleted record space if there are any logical files over the physical file that specify FIFO or LIFO ordering for duplicate keys, or if the physical file has a FIFO or LIFO duplicate key ordering.

• Reusing deleted record space should not be specified for a file that is processed as a direct file or if the file is processed using relative record numbers.

 

Parent topic:

Specifying physical file and member attributes

 

Related concepts

Reorganizing a physical file member
Reusing deleted records

 

Related reference

Change Physical File (CHGPF) command
Change Source Physical File (CHGSRCPF) command
Create Physical File (CRTPF) command
Create Source Physical File (CRTSRCPF) command