Function ExplainCompositeProperties

pg_documentdb/src/index_am/rum.c:1591–1641

static void
ExplainCompositeProperties(void *state, GetMultikeyStatusFunc multiKeyStatusFunc,
						   Relation index_rel, bool enableCompositeReducedCorrelatedTerms,
						   List *indexQuals, List *indexOrderBy, bool
						   supportsOrderedOperatorScans,
						   void (*writeBoolFunc)(const char *, bool, void *),
						   void (*writeStringListFunc)(const char *, List *, void *))
{
	bool isMultiKey = multiKeyStatusFunc ? multiKeyStatusFunc(index_rel) :
					  RumGetMultiKeyStatusSlow(index_rel);
	writeBoolFunc("isMultiKey", isMultiKey, state);

	bool hasCorrelatedTerms = false;
	if (enableCompositeReducedCorrelatedTerms && isMultiKey)
	{
		/* Check if we have correlated reduced terms */
		EnsureRumLibLoaded();
		hasCorrelatedTerms = CheckIndexHasReducedTerms(index_rel, &rum_index_routine);
	}

	if (hasCorrelatedTerms)
	{
		writeBoolFunc("hasCorrelatedTerms", true, state);
	}

	bool isTruncated = RumGetTruncationStatus(index_rel);
	if (isTruncated)
	{
		writeBoolFunc("hasTruncation", true, state);
	}

	Datum compositeDatum = FormCompositeDatumFromQuals(indexQuals, indexOrderBy,
													   isMultiKey, hasCorrelatedTerms,
													   supportsOrderedOperatorScans);
	if (compositeDatum != 0)
	{
		List *rawPerPathBounds = NIL;
		List *boundsList = GetIndexBoundsForExplain(index_rel, compositeDatum,
													list_length(indexOrderBy) > 0,
													&rawPerPathBounds);
		if (rawPerPathBounds != NIL)
		{
			writeStringListFunc("startBounds", boundsList, state);
			writeStringListFunc("rawBounds", rawPerPathBounds, state);
		}
		else
		{
			writeStringListFunc("indexBounds", boundsList, state);
		}
	}
}


static void