Wanted to select data from the table types

Hi,

I wanted to select all the approved BPAs and pick the BPA for a specific vendor ,vendor site and item combination and only pick the latest BPA if there are multiple Approved BPAs existing for that combination.

For this requirement what i have done is i have created the following sql query

SELECT po_header_id, line_num, type_lookup_code
              INTO lv_document_source_id,
                   lv_document_s_line,
                   lv_source_type
              FROM (SELECT pha.po_header_id,
                           pla.line_num,
                           pha.type_lookup_code
                      FROM po_headers_all pha, po_lines_all pla
                     WHERE pla.po_header_id = pha.po_header_id