Function put_view_trigger_blr

src/gpre/cmd.cpp:2681–2745

//

static void put_view_trigger_blr(gpre_req* request,
								 const gpre_rel* relation,
								 USHORT blr_operator,
								 gpre_trg* trigger,
								 gpre_nod* view_boolean, gpre_ctx** contexts)
{
	gpre_rse* node = (gpre_rse*) trigger->trg_boolean;
	request->add_byte(blr_operator);
	const USHORT offset = request->req_blr - request->req_base;
	request->add_word(0);
	if (request->req_flags & REQ_blr_version4)
		request->add_byte(blr_version4);
	else
		request->add_byte(blr_version5);
	request->add_byte(blr_begin);

	if (trigger->trg_type == PRE_MODIFY_TRIGGER)
	{
		request->add_byte(blr_for);
		CME_rse(node, request);

		// For the boolean, replace all fields in the rse and the view, with the
		// equivalent view field_name, for remaining fields in rse, leave them
		// alone.

		replace_field_names(view_boolean, node->rse_fields, relation->rel_fields, false, contexts);

		request->add_byte(blr_begin);
		request->add_byte(blr_if);
		CME_expr(view_boolean, request);

		request->add_byte(blr_begin);
		request->add_byte(blr_end);

		// Generate the action for the trigger to be abort

		request->add_byte(blr_abort);
		put_short_cstring(request, blr_gds_code, "check_constraint");
		request->add_byte(blr_end);
		request->add_byte(blr_end);
		request->add_byte(blr_eoc);
	}							// end of PRE_MODIFY_TRIGGER trigger

	if (trigger->trg_type == PRE_STORE_TRIGGER)
	{
		replace_field_names(view_boolean, node->rse_fields, relation->rel_fields, true, contexts);

		request->add_byte(blr_if);
		CME_expr(view_boolean, request);

		request->add_byte(blr_begin);
		request->add_byte(blr_end);

		// Generate the action for the trigger to be abort

		request->add_byte(blr_abort);
		put_short_cstring(request, blr_gds_code, "check_constraint");
		request->add_byte(blr_end);