you want a report that runs from a parameter, AND you want a blank parameter to mean ALL records.
this is the example I use in a query, I guess it should work for a report. pay attention to the WHERE statement:
Code:
SELECT tbl_spool_file.supplier_in, tbl_spool_file.date_in, tbl_spool_file.po_number, tbl_spool_file.line_po, tbl_spool_file.part_number
FROM tbl_spool_file
WHERE ((([enter a po number]) Is Null)) OR (((tbl_spool_file.po_number)=[enter a po number]) AND (([enter a po number]) Is Not Null))
ORDER BY tbl_spool_file.po_number, tbl_spool_file.line_po;
good luck with your project
Cottonshirt