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GENNUM=

Valid in:	DATA step and PROC steps
Category:	Data Set Control

Syntax Description

integer

is a number that references a specific version from a generation group. Specifying a positive number is an absolute reference to a specific version number that is appended to a data set's name. Specifying a negative number is a relative reference to a version in relation to the base version, from the youngest to the oldest. A value of 0 refers to the current (base) version. Specify an asterisk for integer when you rename the entire generation group for a data set.

Details

After generations for a data set have been requested using the GENMAX= data set option, use GENNUM= to request a specific version. For example, specifying GENNUM=3 refers to the historical version #003, while specifying GENNUM=-1 refers to the youngest historical version.

Note that after 999 replacements, the youngest version would be #999. After 1,000 replacements, SAS rolls over the youngest version number to #000. Therefore, if you want the historical version #000, specify GENNUM=1000.

For more details on generation data sets, see "SAS Data Sets" in SAS Language Reference: Concepts.

Examples

Example 1: Requesting a Version Using an Absolute Reference

This example prints the historical version #003 for data set A, using an absolute reference:

proc print data=a(gennum=3);
run;

Example 2: Requesting A Version Using a Relative Reference

The following PRINT procedure prints the data set three versions back from the base version:

proc print data=a(gennum-3);
run;

Data Set Option: GENMAX=

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