The Duplicate command has a Count Option, whereby you can produce a new field in the output record with the number of occurrences of each key value. The Total Option allows up to 15 fields to be sub-totaled for each duplicate key. For example:
>base store.demo,5,reader >get d-sales {open a dataset} >sort product-no {define a sort key} >duplicate none keys count total sales-qty sales-total >out salessum,link {Output to a link file} >xeqThese commands produce a file with a summary by product-no (because that is what we sorted by). The file will contain a count of the number of records for that product-no, and totals for the sales-qty and sales-total.
The count field is called ST-COUNT and the totals have field names of ST-TOTAL-1 and ST-TOTAL-2, which are at the end of each record.