Reading Multiple Raw Data Files

Q.  Can I read multiple raw data files in a DATA step to create a combined SAS data set, all my files have the same data layout?

A.  If a number of raw data files have the same data layout, all of those files can be included in a FILENAME statement and assigned a single fileref. When this fileref is included in a Data step, SAS can read those input raw data files sequentially.

For example, some of the census data have a separate raw data file for each state, all state files have a similar data layout. To create a combined SAS data set for US, the raw data files can be included in a FILENAME statement to be read in a Data step. Here is an example.

FILENAME myfiles ("c:\mydir\one.dat", "c:\mydir\two.dat", "c:\mydir\three.dat");
DATA  temp1;
   INFILE myfiles lrecl=331;
   INPUT var1 10-15 var2 22-30 var3 98-100;
RUN;

With SAS 8.2 you can also use wildcards in your FILENAME statement like this:

filename myfiles ("c:\mydir\*.csv");
filename myfiles ("c:\mydir\test*.dat");
filename myfiles ("c:\mydir\*.*");