The following lines contain the word 'select', 'insert', 'update' or 'delete':
SELECT 'valid'
FROM po_headers
WHERE po_header_id = x_po_header_id
AND (TRUNC(x_effective_date) BETWEEN
TRUNC(nvl(start_date,x_effective_date)) AND
TRUNC(nvl(end_date, x_effective_date)));
UPDATE po_unique_identifier_cont_all
SET current_max_unique_identifier =
current_max_unique_identifier +1
WHERE table_name = p_table_name
AND org_id = p_org_id
RETURNING current_max_unique_identifier
INTO l_po_unique_identifier_v;