Comparing SAS System 9 to Earlier Releases

SAS 9 File Format

In order to provide longer file names and variable names , the file format used in SAS 7 and 8 is different from the file format used in SAS 6.

For SAS 9, the file format is basically the same as in SAS 7 and 8. The Base SAS engine is the same engine, except that for SAS 9, you can define and use longer format and informat names. You cannot use longer format and informat names in SAS 7 or 8.

SAS files created with SAS 7 and 8 are compatible with SAS 9. However, a SAS file that is created with a 32-bit version of SAS has a different data representation than a SAS file from a 64-bit version of SAS. The data representation is the format in which data is represented on a computer architecture or in an operating environment. Therefore, if you have SAS files that were created on a 32-bit version of SAS and you have upgraded to a 64-bit version of SAS, you will have processing limitations due to the different data representation.

SAS 9 Filename Extensions

A filename extension reflects the engine that was used to create both the file and the SAS file member type.

Because SAS needs to distinguish among the different file types and versions, SAS automatically assigns a specific extension to each file when the file is created. For example, in order to distinguish SAS 7 and 8 files from SAS 6 files, the extensions are different.

For SAS 9, the file extensions are the same as the file extensions in SAS 7 and 8.

The following table lists the file extensions for a SAS data file (SAS data set with member type DATA) in SAS 6, 7, 8, and 9 for different operating environments:

Table 35.1: File Extensions for a SASData File in DifferentOperating Environments

Engine Name	UNIX	OpenVMS Alpha	Windows	z/OS [1]
V6	.ssd01	.SASEB$DATA	.sd2	not available
V7	.sas7bdat	.sas7bdat	.sas7bdat	.sas7bdat
V8	.sas7bdat	.sas7bdat	.sas7bdat	.sas7bdat
V9	.sas7bdat	.sas7bdat	.sas7bdat	.sas7bdat
[1] applies to SAS data sets that reside in the hierarchical file system of UNIX System Services.

Operating Environment Information: For a complete list of SAS member types and extensions, see the SAS documentation for your operating environment.