Method matchOnIndexes

src/jrd/optimizer/Retrieval.cpp:2232–2411

//

InversionCandidate* Retrieval::matchOnIndexes(IndexScratchList& inputIndexScratches,
											  BoolExprNode* boolean,
											  unsigned scope) const
{
	const auto binaryNode = nodeAs<BinaryBoolNode>(boolean);

	// Handle the "OR" case up front
	if (binaryNode && binaryNode->blrOp == blr_or)
	{
		InversionCandidateList inversions;

		// Make list for index matches

		// Copy information from caller
		IndexScratchList indexOrScratches(inputIndexScratches);

		// We use a scope variable to see on how
		// deep we are in a nested or conjunction.
		scope++;

		auto invCandidate1 = matchOnIndexes(indexOrScratches, binaryNode->arg1, scope);

		if (invCandidate1)
			inversions.add(invCandidate1);

		auto childBoolNode = nodeAs<BinaryBoolNode>(binaryNode->arg1);

		// Get usable inversions based on indexOrScratches and scope
		if (!childBoolNode || childBoolNode->blrOp != blr_or)
			getInversionCandidates(inversions, indexOrScratches, scope);

		invCandidate1 = makeInversion(inversions);

		// Copy information from caller
		indexOrScratches = inputIndexScratches;

		// Clear inversion list
		inversions.clear();

		auto invCandidate2 = matchOnIndexes(indexOrScratches, binaryNode->arg2, scope);

		if (invCandidate2)
			inversions.add(invCandidate2);

		childBoolNode = nodeAs<BinaryBoolNode>(binaryNode->arg2);

		// Make inversion based on indexOrScratches and scope
		if (!childBoolNode || childBoolNode->blrOp != blr_or)
			getInversionCandidates(inversions, indexOrScratches, scope);

		invCandidate2 = makeInversion(inversions);

		if (invCandidate1 && invCandidate2 &&
			(invCandidate1->indexes || invCandidate1->unique) &&
			(invCandidate2->indexes || invCandidate2->unique))
		{
			const auto invCandidate = FB_NEW_POOL(getPool()) InversionCandidate(getPool());
			invCandidate->inversion = composeInversion(invCandidate1->inversion,