Join the AP_Holds_All and Ap_Invoice_lines_All

Hi

We joined the query AP_Holds_All and Ap_Invoice_lines_All Table based on the below query (Example)

Select A.* From Ap_Invoice_lines_all A, Ap_Holds_All B

   Where A.Po_Line_Location_id = B.Line_Location_Id

     And B.Status_Flag <> 'R'

     And A.Invoice_id ='15227152'

     Order by A.Line_number

If Line_Location_Id & Po_Line_Location_Id is Null in the Ap_Holds_All and Ap_Invoice_lines_All table.

How to join both tables (AP_Holds_All and Ap_Invoices_Lines_All). Please help me.

Regards

M.Padmanabhan