DRGFilt respects a "control file" which tells it how to pick out its input fields from each record and were to put its output fields into each record. Typically, you assign DRGs to an entire data set with the following steps:

• Export your data from your database into an ASCII text file
• Create a DRGFilt control file to match your data
• Run DRGFilt on your ASCII text file, which produces a new ASCII text file
• Input the new ASCII text file into your database