Support ORDER BY ... NULLS FIRST/LAST, and add ASC/DESC/NULLS FIRST/NULLS LAST

per-column options for btree indexes.  The planner's support for this is still
pretty rudimentary; it does not yet know how to plan mergejoins with
nondefault ordering options.  The documentation is pretty rudimentary, too.
I'll work on improving that stuff later.

Note incompatible change from prior behavior: ORDER BY ... USING will now be
rejected if the operator is not a less-than or greater-than member of some
btree opclass.  This prevents less-than-sane behavior if an operator that
doesn't actually define a proper sort ordering is selected.

1 files changed, 7 insertions, 7 deletions

diff --git a/src/backend/commands/analyze.c b/src/backend/commands/analyze.c
index 102be0d96fe..c568f04284c 100644
--- a/src/backend/commands/analyze.c
+++ b/src/backend/commands/analyze.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/analyze.c,v 1.102 2007/01/05 22:19:25 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/analyze.c,v 1.103 2007/01/09 02:14:11 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1297,7 +1297,7 @@ typedef struct
 typedef struct
 {
 	FmgrInfo   *cmpFn;
-	SortFunctionKind cmpFnKind;
+	int			cmpFlags;
 	int		   *tupnoLink;
 } CompareScalarsContext;
 
@@ -1747,8 +1747,8 @@ compute_scalar_stats(VacAttrStatsP stats,
 	bool		is_varwidth = (!stats->attr->attbyval &&
 							   stats->attr->attlen < 0);
 	double		corr_xysum;
-	RegProcedure cmpFn;
-	SortFunctionKind cmpFnKind;
+	Oid			cmpFn;
+	int			cmpFlags;
 	FmgrInfo	f_cmpfn;
 	ScalarItem *values;
 	int			values_cnt = 0;
@@ -1763,7 +1763,7 @@ compute_scalar_stats(VacAttrStatsP stats,
 	tupnoLink = (int *) palloc(samplerows * sizeof(int));
 	track = (ScalarMCVItem *) palloc(num_mcv * sizeof(ScalarMCVItem));
 
-	SelectSortFunction(mystats->ltopr, &cmpFn, &cmpFnKind);
+	SelectSortFunction(mystats->ltopr, false, &cmpFn, &cmpFlags);
 	fmgr_info(cmpFn, &f_cmpfn);
 
 	/* Initial scan to find sortable values */
@@ -1833,7 +1833,7 @@ compute_scalar_stats(VacAttrStatsP stats,
 
 		/* Sort the collected values */
 		cxt.cmpFn = &f_cmpfn;
-		cxt.cmpFnKind = cmpFnKind;
+		cxt.cmpFlags = cmpFlags;
 		cxt.tupnoLink = tupnoLink;
 		qsort_arg((void *) values, values_cnt, sizeof(ScalarItem),
 				  compare_scalars, (void *) &cxt);
@@ -2203,7 +2203,7 @@ compare_scalars(const void *a, const void *b, void *arg)
 	CompareScalarsContext *cxt = (CompareScalarsContext *) arg;
 	int32		compare;
 
-	compare = ApplySortFunction(cxt->cmpFn, cxt->cmpFnKind,
+	compare = ApplySortFunction(cxt->cmpFn, cxt->cmpFlags,
 								da, false, db, false);
 	if (compare != 0)
 		return compare;