DBMS_XMLGEN.GETXML is not providing the xml output.

Am trying to generate a xml report for a sql query, am Trying to use DBMS_XMLGEN.GETXML to get the xml output but its not working when i run the concurrent program.

Am getting an numeric or vaalue error. please help me in finding the issue.

Here is the script i use.

 

      vl_qryctx := dbms_xmlgen.NEWCONTEXT(' SELECT DISTINCT aia.invoice_num, aia.invoice_date,

                                                         asa.segment1,

                         asa.vendor_name, aia.gl_date,

                         aia.payment_status_flag, aia.invoice_amount,

                         aida.amount,                        

                         (aida.attribute3'|| '-' || ' aida.attribute2

                         ) po_receipt,

                         hru.NAME, gcc.concatenated_segments

                    FROM apps.ap_invoices_all aia,