Function create_index_path

src/backend/optimizer/util/pathnode.c:1105–1149

* create_index_path * Creates a path node for an index scan. * * 'index' is a usable index. * 'indexclauses' is a list of IndexClause nodes representing clauses * to be enforced as qual conditions in the scan. * 'indexorderbys' is a list of bare expressions (no RestrictInfos) * to be used as index ordering operators in the scan. * 'indexorderbycols' is an integer list of index column

 * Returns the new path node.
 */
IndexPath *
create_index_path(PlannerInfo *root,
				  IndexOptInfo *index,
				  List *indexclauses,
				  List *indexorderbys,
				  List *indexorderbycols,
				  List *pathkeys,
				  ScanDirection indexscandir,
				  bool indexonly,
				  Relids required_outer,
				  double loop_count,
				  bool partial_path)
{
	IndexPath  *pathnode = makeNode(IndexPath);
	RelOptInfo *rel = index->rel;

	pathnode->path.pathtype = indexonly ? T_IndexOnlyScan : T_IndexScan;
	pathnode->path.parent = rel;
	pathnode->path.pathtarget = rel->reltarget;
	pathnode->path.param_info = get_baserel_parampathinfo(root, rel,
														  required_outer);
	pathnode->path.parallel_aware = false;
	/* GPDB_12_MERGE_FEATURE_NOT_SUPPORTED: the parallel StreamBitmap scan is not implemented */
	pathnode->path.parallel_safe = rel->consider_parallel && !IsIndexAccessMethod(index->relam, BITMAP_AM_OID);
	pathnode->path.parallel_workers = 0;
	pathnode->path.pathkeys = pathkeys;

	pathnode->indexinfo = index;
	pathnode->indexclauses = indexclauses;
	pathnode->indexorderbys = indexorderbys;
	pathnode->indexorderbycols = indexorderbycols;
	pathnode->indexscandir = indexscandir;

	/* Distribution is same as the base table. */
	pathnode->path.motionHazard = false;
	pathnode->path.barrierHazard = false;
	pathnode->path.rescannable = true;
	pathnode->path.sameslice_relids = rel->relids;

	cost_index(pathnode, root, loop_count, partial_path);

	pathnode->path.locus = cdbpathlocus_from_baserel(root, rel, partial_path ? pathnode->path.parallel_workers : 0);

	return pathnode;
}

/*
 * create_bitmap_heap_path