>I need some assistance with the deletion of duplicate records. I am working with a free table (no primary keys).
>
>What I am trying to accomplish is finding a prg to seek out all the duplicate values in the invoice_no field and delete them.
>
>can someone help me out?

Get duplicates:

select invoice_num, count(*) as ncnt ;
  from mytable ;
  group by invoice_num ;
  having count(*) > 1 ;
  into cursor cudupes

Which dupe to delete is another question. Assuming for this example that you want to keep the first entry of an invoice number and delete the rest:

SELECT mytable  
SET ORDER TO invoice_no && assuming there is an index on this, at least
SELECT cudupes

SCAN
  lcInv = invoice_no
  =SEEK(lcInv, "mytable")
  SKIP IN mytable
  DELETE WHILE invoice_no = lcInv IN mytable
ENDSCAN

For the future, I would suggest making the invoice_num index a CANDIDATE key, then trap for any candidate key violations when creating new invoice numbers.