Method calculateStreamInfo

src/jrd/optimizer/InnerJoin.cpp:86–168

//

void InnerJoin::calculateStreamInfo()
{
	StreamList streams;

	// First get the base cost without any relation to any other inner join stream

#ifdef OPT_DEBUG_RETRIEVAL
	optimizer->printf("Base stream info:\n");
#endif

	const auto sort = sortPtr ? *sortPtr : nullptr;

	for (auto innerStream : innerStreams)
	{
		streams.add(innerStream->number);
		csb->csb_rpt[innerStream->number].activate();

		Retrieval retrieval(tdbb, optimizer, innerStream->number, false, false, sort, true);
		const auto candidate = retrieval.getInversion();

		innerStream->baseCost = candidate->cost;
		innerStream->baseSelectivity = candidate->selectivity;
		innerStream->baseIndexes = candidate->indexes;
		innerStream->baseUnique = candidate->unique;
		innerStream->baseNavigated = candidate->navigated;
		innerStream->baseMatches = candidate->matches;
		innerStream->baseDependentFromStreams = candidate->dependentFromStreams;

		csb->csb_rpt[innerStream->number].deactivate();
	}

	// Collect dependencies between every pair of streams

	for (const auto baseStream : streams)
	{
		csb->csb_rpt[baseStream].activate();

		for (const auto innerStream : innerStreams)
		{
			const StreamType testStream = innerStream->number;

			if (baseStream != testStream)
			{
				csb->csb_rpt[testStream].activate();
				getIndexedRelationships(innerStream);
				csb->csb_rpt[testStream].deactivate();
			}
		}

		csb->csb_rpt[baseStream].deactivate();
	}

	// Collect more complex inter-dependencies (involving three and more streams), if any

	if (streams.getCount() > 2)
	{
		StreamStateHolder stateHolder(csb, streams);
		stateHolder.activate();