SAS FAQ
How do I convert a SAS version 8 file to SAS version 6 (using Windows)?

Say that you have a data file called c:\dissertation\salary8.sas7bdat.  Because the extension of the file is .sas7bdat we know it is a SAS 8.xx file. You may want to use this file somewhere where you only have SAS version 6 and need to convert it to a SAS version 6 file. You can do this as shown in the example below. Note that the v6 indicates that out will read/write SAS version 6 files, so when we say out.salary6 this tells SAS that we want to create a SAS version 6 file.

libname out v6 'c:\dissertation\';
data out.salary6;
  set 'c:\dissertation\salary8';
run;
 
proc print data=out.salary6;
run;
 
proc contents data=out.salary6;
run;

We can see from the output below that salary6 was successfully created and it is a SAS version 6.x file that can be read under SAS version 6.x.

Obs    SAL1996    SAL1997    SAL1998    SAL1999    SAL2000
 1      10000      10500      11000      12000      12700
 2      14000      16500      18000      22000      29000
The CONTENTS Procedure

Data Set Name: OUT.SALARY6                                Observations:         2
Member Type:   DATA                                       Variables:            5
Engine:        V6                                         Indexes:              0
Created:       16:53 Thursday, November 16, 2000          Observation Length:   40
Last Modified: 16:53 Thursday, November 16, 2000          Deleted Observations: 0
Protection:                                               Compressed:           NO
Data Set Type:                                            Sorted:               NO
Label:

     -----Engine/Host Dependent Information-----

 <output edited to save space> 
File Name:                  c:\dissertation\salary6.sd2
Release Created:            6.08.00
Host Created:               WIN

-----Alphabetic List of Variables and Attributes-----

#    Variable    Type    Len    Pos
-----------------------------------
1    SAL1996     Num       8      0
2    SAL1997     Num       8      8
3    SAL1998     Num       8     16
4    SAL1999     Num       8     24
5    SAL2000     Num       8     32

It is possible that your SAS version 8 file might have contained long variable names, a feature available in version 8 but not available in version 6. Say that you have a data file called c:\dissertation\salaryl.sas7bdat that contains long variable names. If we try to convert it the same way that we did in the example above, it does not work.

data out.salary6;
  set 'c:\dissertation\salaryl';
run;

Running this we get the following error message in the log.

ERROR: The variable name Salary1996 is illegal for the version 6 file ;
        OUT.SALARY6.DATA. ;
NOTE: The SAS System stopped processing this step because of errors. ; 

In this case, we need to use the validvarname=v6 option to tell SAS to use/create variable names that are compatible with SAS version 6 and to use proc copy to copy the data file, as illustrated in the example below.

options validvarname=v6;
libname diss8 v8 'c:\dissertation\';
libname diss6 v6 'c:\dissertation\';
 
proc copy in=diss8 out=diss6 ;
  select salaryl;
run;
 
proc print data=diss6.salaryl;
run;
 
proc contents data=diss6.salaryl;
run;

As we can see from the output below, we were able to successfully convert the data file to a version 6 data file. SAS converted the long variable names into 8 character variable names. The conversion led to some variable names that were not very intuitive so be sure to inspect the proc contents. As you see below, the proc contents includes a variable label that shows the name of the variable before it was converted.

Obs    SALARY19    SALARY12    SALARY13    SALARY14    SALARY20
 1       10000       10500       11000       12000       12700
 2       14000       16500       18000       22000       29000
The CONTENTS Procedure

Data Set Name: DISS6.SALARYL                              Observations:         2
Member Type:   DATA                                       Variables:            5
Engine:        V6                                         Indexes:              0
Created:       16:53 Thursday, November 16, 2000          Observation Length:   40
Last Modified: 16:53 Thursday, November 16, 2000          Deleted Observations: 0
Protection:                                               Compressed:           NO
Data Set Type:                                            Sorted:               NO
Label:

      -----Engine/Host Dependent Information-----
 <output edited to save space> 
File Name:                  c:\dissertation\salaryl.sd2
Release Created:            6.08.00
Host Created:               WIN
-----Alphabetic List of Variables and Attributes-----

#    Variable    Type    Len    Pos    Label
-------------------------------------------------
2    SALARY12    Num       8      8    Salary1997
3    SALARY13    Num       8     16    Salary1998
4    SALARY14    Num       8     24    Salary1999
1    SALARY19    Num       8      0    Salary1996
5    SALARY20    Num       8     32    Salary2000

For more information

• SAS FAQ  
  - How do I read SAS Version 6 files using SAS version 8, How do I convert SAS Version 6 Files to SAS Version 8 (under windows)
• SAS Learning Modules
  - Making and Using Permanent SAS Data Files (version 8)
  - Making and Using SAS Data Files (version 6)