Method evaluateBoolean

src/jrd/recsrc/FilteredStream.cpp:193–419

}

bool FilteredStream::evaluateBoolean(thread_db* tdbb) const
{
	Request* const request = tdbb->getRequest();

	// For ANY and ALL clauses (ALL is handled as a negated ANY),
	// we must first detect them, and then make sure that the returned
	// results are correct. This mainly entails making sure that
	// there are in fact records in the source stream to test against.
	// If there were none, the response must be FALSE.
	// Also, if the result of the column comparison is always
	// NULL, this must also be returned as NULL.
	// (Note that normally, an AND of a NULL and a FALSE would be FALSE, not NULL).

	// This all depends on evl.cpp putting the unoptimized expression
	// in the rsb. The unoptimized expression always has the
	// select expression on the left, and the column comparison
	// on the right.

	// ANY/ALL select node pointer
	const BoolExprNode* select_node;

	// ANY/ALL column node pointer
	const BoolExprNode* column_node = m_anyBoolean;

	if (column_node && (m_ansiAny || m_ansiAll))
	{
		// see if there's a select node to work with

		const BinaryBoolNode* booleanNode = nodeAs<BinaryBoolNode>(column_node);

		if (booleanNode && booleanNode->blrOp == blr_and)
		{
			select_node = booleanNode->arg1;
			column_node = booleanNode->arg2;
		}
		else
			select_node = NULL;
	}

	if (column_node && m_ansiAny)
	{
		if (m_ansiNot)
		{
			// do NOT ANY
			// if the subquery was the empty set
			// (numTrue + numFalse + numUnknown = 0)
			// or if all were false
			// (numTrue + numUnknown = 0),
			// NOT ANY is true

			bool any_null = false;	// some records true for ANY/ALL
			bool any_true = false;	// some records true for ANY/ALL

			while (m_next->getRecord(tdbb))
			{
				if (m_boolean->execute(tdbb, request))
				{
					// found a TRUE value