Method internalGetRecord

src/jrd/recsrc/NestedLoopJoin.cpp:101–243

}

bool NestedLoopJoin::internalGetRecord(thread_db* tdbb) const
{
	JRD_reschedule(tdbb);

	Request* const request = tdbb->getRequest();
	Impure* const impure = request->getImpure<Impure>(m_impure);

	if (!(impure->irsb_flags & irsb_open))
		return false;

	if (m_joinType == INNER_JOIN)
	{
		if (impure->irsb_flags & irsb_first)
		{
			for (FB_SIZE_T i = 0; i < m_args.getCount(); i++)
			{
				m_args[i]->open(tdbb);

				if (!fetchRecord(tdbb, i))
					return false;
			}

			impure->irsb_flags &= ~irsb_first;
		}
		// hvlad: self referenced members are removed from recursive SELECT's
		// in recursive CTE (it is done in dsql\pass1.cpp). If there are no other
		// members in such SELECT then rsb_count will be zero. Handle it.
		else if (m_args.isEmpty())
			return false;
		else if (!fetchRecord(tdbb, m_args.getCount() - 1))
			return false;
	}
	else if (m_joinType == SEMI_JOIN || m_joinType == ANTI_JOIN)
	{
		const auto outer = m_args[0];

		if (impure->irsb_flags & irsb_first)
		{
			outer->open(tdbb);

			impure->irsb_flags &= ~irsb_first;
		}

		while (true)
		{
			if (impure->irsb_flags & irsb_joined)
			{
				for (FB_SIZE_T i = 1; i < m_args.getCount(); i++)
					m_args[i]->close(tdbb);

				impure->irsb_flags &= ~irsb_joined;
			}

			if (!outer->getRecord(tdbb))
				return false;

			FB_SIZE_T stopArg = 0;