77 *
88 *
99 * IDENTIFICATION
10- * $Header: /cvsroot/pgsql/src/backend/optimizer/plan/createplan.c,v 1.65 1999/07/29 02:48:05 tgl Exp $
10+ * $Header: /cvsroot/pgsql/src/backend/optimizer/plan/createplan.c,v 1.66 1999/07/30 00:44:23 tgl Exp $
1111 *
1212 *-------------------------------------------------------------------------
1313 */
@@ -296,10 +296,13 @@ create_seqscan_node(Path *best_path, List *tlist, List *scan_clauses)
296296 * Returns a indexscan node for the base relation scanned by 'best_path'
297297 * with restriction clauses 'scan_clauses' and targetlist 'tlist'.
298298 *
299- * If an 'or' clause is to be used with this index, the indxqual field
300- * will contain a list of the 'or' clause arguments, e.g., the
301- * clause(OR a b c) will generate: ((a) (b) (c)). Otherwise, the
302- * indxqual will simply contain one conjunctive qualification: ((a)).
299+ * The indexqual of the path contains a sublist of implicitly-ANDed qual
300+ * conditions for each scan of the index(es); if there is more than one
301+ * scan then the retrieved tuple sets are ORed together. The indexqual
302+ * and indexid lists must have the same length, ie, the number of scans
303+ * that will occur. Note it is possible for a qual condition sublist
304+ * to be empty --- then no index restrictions will be applied during that
305+ * scan.
303306 */
304307static IndexScan *
305308create_indexscan_node (IndexPath * best_path ,
@@ -316,7 +319,7 @@ create_indexscan_node(IndexPath *best_path,
316319/* there should be exactly one base rel involved... */
317320Assert (length (best_path -> path .parent -> relids )== 1 );
318321
319- /* check and see if any indices are lossy */
322+ /* check and see if anyof the indices are lossy */
320323foreach (ixid ,best_path -> indexid )
321324{
322325HeapTuple indexTuple ;