Control File Maintenance Utility › Control File Statements › ADD Statement (VSAM)

ADD Statement (VSAM)

The ADD statement for VSAM defines a cluster or pattern to CA Compress, indicating that the discrete data set(s) matching the pattern should be compressed using the attributes specified.

ADD	{DSNAME=datasetname,DATA=datacomponentname}|
	{PATTERN=patternname}
	[,PATHS=(pathname1[,pathname2...
	{,SUPEREXP|
	FDT=fdtname[,STANDARD]|DICTIONARY=dictionary}
	[,SCHEDULED={SCHED|OPEN|LOAD}]
	[,EXCLUDE]
	[,RELEASE=percent]
	[,NON-COMP=#]
	[,SCOPE=CICS|ALL]
	[,IAM=YES|NO]
	[,UEXIT=YES|NO]

DSNAME=datasetname

Specifies a VSAM cluster which is to be compressed. The DATA parameter is required when the DSNAME parameter is specified.

DATA=datacomponentname

Specifies the data component of the VSAM cluster specified by DSNAME. This parameter is required when the DSNAME parameter is specified.

PATTERN=patternname

Specifies a data set name pattern which selects data sets for compression. The pattern can contain any character that is valid in a data set name along with the special characters ?, *, ! and /. These special characters are defined in the section Syntax Rules in this chapter.

PATHS=(pathname1 [,pathname2 ...

Specifies all path names associated with the DSNAME. This parameter is required if there are any paths defined for this cluster. A maximum of 20 path names can be specified.

SUPEREXP|FDT=fdtname[,STANDARD]|DICTIONARY=dictionary

Selects the type of compression desired for the data set or pattern being defined.

The optional parameter STANDARD can be specified only in conjunction with the FDT=fdtname parameter. It informs the CA Compress Subsystem that the FDT specified should be used to provide the compression or expansion tables only, and that the RDL specified in the FDT should be ignored. The STANDARD parameter allows one FDT to be used for a number of data sets that share character distribution characteristics but not key structure. STANDARD is implied if the FDT parameter specifies a name of the form STDTBLxx (where xx is a numeric value from 01 to 06).

The DICTIONARY parameter can specify a CA-supplied IBM Hardware Compression dictionary of the form HC#STDxx (where xx is numeric 01 to 05).

SUPEREXP specifies the low-overhead compression algorithm called Super Express.

SCHEDULED={SCHED|OPEN|LOAD}

The SCHEDULED parameter provides the capability to compress records in a data set as they are written or updated. OPEN specifies that the data set be compressed the next time it is opened for OUTPUT. LOAD specifies that compression should begin the next time the data set is completely reloaded; the entire data set will be compressed during the load process. SCHED specifies that the data set is currently compressed and was compressed as SCHEDULED. Because SCHEDULED data sets have certain requirements, CA Compress must be made aware that these data sets were originally SCHEDULED. The compression method for a data set defined as SCHEDULED can be changed using the ALTER statement any time before compression begins.

EXCLUDE

Specifies that the data set is excluded from compression.

RELEASE=percent

Specifies that excess space should be released from the VSAM cluster. It is also used to provide the percentage of the space that is to be RETAINED. The percentage is applied to the file size (high-used RBA) and the resulting value is added to the file size; the resulting value is the amount retained. Space can only be released from the last extent of the data set.

Note: A RELEASE value of 0 causes the default value (10%) to be used.

NON-COMP=#

Specifies a data set's original noncompressible field length for other than custom Huffman or Tailored RDL methods instead of allowing CA Compress to calculate it from the data set's attributes. This parameter is especially helpful for exempting nonkey bytes from compression or for setting aside noncompressible bytes at the beginning of ESDS records. Do not code a value less than the end of the last key.

SCOPE=CICS|ALL

Specifies whether data set should be considered defined as compressed only under CICS (SCOPE=CICS) or always (SCOPE=ALL). This parameter is primarily intended as a conversion aid. The default is SCOPE=ALL.

IAM=YES|NO

Specifies that this Control File entry applies to IAM (Innovation Access Method) data sets as well as VSAM data sets (YES), or that this entry does not apply to IAM data sets (NO). The default is YES.

UEXIT=YES|NO

Specifies whether the Transparency User Exit is to be invoked during compression and expansion of each record. The default is NO.