SAS 9.4 Language Reference, 6th Edition

Comparing SAS 9 to Earlier Releases

SAS 9 File Format

To provide longer filenames and variable names, the file format used in SAS 7 and SAS

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 SAS 8. The Base SAS

engine is the same engine, except that for SAS 9, you can define and use longer format

and informat names and have more than 32,767 variables in a SAS data set. You cannot

use these features in SAS 7 or SAS 8.

SAS files created with SAS 7 and SAS 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 have processing limitations due to the

different data representation.

You might be able to use the EXTENDOBSCOUNTER= data set option to resolve some

compatibility issues between files that are generated in SAS 9.4 and those from earlier

releases. For more information, see the following resources:

• “Backward Compatibility of the Extended Observation Count Attribute” on page 618

• “EXTENDOBSCOUNTER= Data Set Option” in SAS Data Set Options: Reference

SAS 9 File Extensions

A file 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 SAS 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 SAS 8.

The following table lists the file extensions for a SAS data file (SAS data set with

member type DATA) in SAS 6, SAS 7, SAS 8, and SAS 9 for different operating

environments:

Table 35.1 File Extensions for a SAS Data File in Different Operating Environments

Engine Name UNIX Windows z/OS

*

V6 .ssd01 .sd2 not available

V7 .sas7bdat .sas7bdat .sas7bdat

V8 .sas7bdat .sas7bdat .sas7bdat

726 Chapter 35 • SAS 9.4 Compatibility with SAS Files from Earlier Releases