Query : Invoices on hold

select distinct
ai.invoice_num,ai.invoice_amount,ai.invoice_date
,ai.invoice_received_date,ah.hold_lookup_code,ah.hold_reason,pv.vendor_name,pv.segment1 vendor_number
,ph.segment1 po_number
,gcc.segment1||'.'||gcc.segment2||'.'||gcc.segment3||'.'||gcc.segment4||'.'||gcc.segment5||'.'||gcc.segment6
--,aid.AMOUNT
from ap_invoices_all ai
,ap_holds_all ah
,po_vendors pv
,po_headers_all ph
,ap_invoice_distributions_all aid
,po_distributions_all pda
,gl_code_combinations gcc
where 1=1
and ai.invoice_id = ah.invoice_id
and ai.vendor_id = pv.vendor_id
--and ai.po_header_id = ph.po_header_id(+)
and ph.PO_HEADER_ID = pda.PO_HEADER_ID
and ah.invoice_id = aid.invoice_id
and aid.po_distribution_id = pda.po_distribution_id
and aid.dist_code_combination_id = gcc.code_combination_id