In the following program, data compression is specified for transfile but not for masterfile. For key compression, suppression of trailing spaces and of leading characters that are the same as in the previous key is specified for keys t-rec-key and m-rec-key. Suppression of repetition of duplicate keys is also turned on for m-alt-key-1 and m-alt-key-2.
$set callfh"extfh" $set datacompress"1" $set keycompress"6" select transfile assign to ... key is t-rec-key. $set nokeycompress $set nodatacompress
select masterfile assign to ... organization is indexed $set keycompress"6" record key is m-rec-key
$set keycompress"7" alternate key is m-alt-key-1 with duplicates alternate key is m-alt-key-2. $set nokeycompress