Function evlMakeDbkey

src/jrd/SysFunction.cpp:5423–5520

dsc* evlMakeDbkey(Jrd::thread_db* tdbb, const SysFunction* function, const NestValueArray& args, Jrd::impure_value* impure)
{
	// MAKE_DBKEY ( REL_NAME | REL_ID, RECNUM [, DPNUM [, PPNUM] ] )

	Database* const dbb = tdbb->getDatabase();
	Request* const request = tdbb->getRequest();

	fb_assert(args.getCount() >= 2 && args.getCount() <= 4);

	dsc* argDsc = EVL_expr(tdbb, request, args[0]);
	if (request->req_flags & req_null)	// return NULL if relation is NULL
		return NULL;

	USHORT relId;

	if (argDsc->isText())
	{
		MetaName relName;
		CVT2_make_metaname(argDsc, relName, tdbb->getAttachment()->att_dec_status);

		const jrd_rel* const relation = MET_lookup_relation(tdbb, relName);
		if (!relation)
			(Arg::Gds(isc_relnotdef) << Arg::Str(relName)).raise();

		relId = relation->rel_id;
	}
	else
	{
		const SLONG value = MOV_get_long(tdbb, argDsc, 0);
		if (value < 0 || value > MAX_USHORT) // return NULL if the provided ID is too long
			return NULL;

		relId = (USHORT) value;
	}

	argDsc = EVL_expr(tdbb, request, args[1]);
	if (request->req_flags & req_null)
		return NULL;

	SINT64 recNo = MOV_get_int64(tdbb, argDsc, 0);

	SINT64 dpNum = 0, ppNum = 0;

	if (args.getCount() > 2)
	{
		argDsc = EVL_expr(tdbb, request, args[2]);
		if (request->req_flags & req_null)
			return NULL;

		dpNum = MOV_get_int64(tdbb, argDsc, 0);
		if (dpNum > MAX_ULONG)
			return NULL;
	}

	if (args.getCount() > 3)
	{
		argDsc = EVL_expr(tdbb, request, args[3]);
		if (request->req_flags & req_null)