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COMPRESS

Specifies whether compression was used when the input or output data file was created.
Note: Supported by the following mfims imsdbu functions:
  • Add
  • Load
  • Unload

Syntax:

>>-.---.-.-------COMPRESS--(program)--.-----><
   +-/-+ +.----.-COMPRESS-------------+
          +-NO-+

Parameters:

program
The name of a compression/expansion routine to use instead of the system-supplied routine.

Properties:

Default: NOCOMPRESS

Comments:

The COMPRESS directive enables or disables the expansion of the input data file records.

The COMPRESS directive is only used when when LAYOUT(G) is specified. It is not required and is ignored when LAYOUT(D), LAYOUT(I) or LAYOUT(S) is specified.

Specifying COMPRESS with no program name causes decompression using the CBLDCIMS program (built-in to the MFIMS software libraries). You can override the name of the compression/expansion routine by specifying a user-written program name.

Add and Load functions
The compression directive for loading must match the setting used when creating the input file. The compression settings are ignored when loading LAYOUT(D) input files as the compression setting is stored in the unload file header record. For generic format loads, ensure that the COMPRESS directive is set correctly to avoid data corruption.
Unload function
When using an Unload file for a subsequent Load, the compression directive used for unloading must also be used when loading. For the IMSDBU-specific LAYOUT(D) formats, this is automatic as the compression setting is stored in the unload file header record. For generic format unloads, ensure that the COMPRESS directive is set correctly to avoid data corruption.
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