fixes for issues #7447 and #7448

ranges queries can have null's and not return NULL, ie fixed optimizer/statistics
only use full hash index for selects

sql/backends/monet5/rel_bin.c

@@ -2592,6 +2592,8 @@ rel2bin_hash_lookup(backend *be, sql_rel *rel, stmt *left, stmt *right, sql_idx
 			h = stmt_unop(be, s, NULL, hf);
 		}
 	}
+	if (n != NULL) /* need to use all cols of the index */
+		return NULL;
 	if (h && h->nrcols) {
 		if (!swap_rel) {
 			return stmt_join(be, idx, h, 0, cmp_equal, 0, semantics, false);

sql/server/rel_statistics.c

@@ -33,6 +33,10 @@ comparison_find_column(sql_exp *input, sql_exp *e)
 	}
 }
 
+/* multi lo <= col <= hi, maybe still be false even if lo or hi are NULL, possibly similar for filter on multiple
+ * columns */
+#define comp_single_column(c) (!c->f)
+
 static sql_exp *
 rel_propagate_column_ref_statistics(mvc *sql, sql_rel *rel, sql_exp *e)
 {
@@ -69,7 +73,7 @@ rel_propagate_column_ref_statistics(mvc *sql, sql_rel *rel, sql_exp *e)
 								*rval_min = find_prop_and_get(re->p, PROP_MIN), *rval_max = find_prop_and_get(re->p, PROP_MAX);
 
 							/* not semantics found or if explicitly filtering not null values from the column */
-							found_without_semantics |= !is_semantics(comp) || (comp->flag == cmp_equal && lne && is_anti(comp) && exp_is_null(re));
+							found_without_semantics |= (!is_semantics(comp) && comp_single_column(comp)) || (comp->flag == cmp_equal && lne && is_anti(comp) && exp_is_null(re));
 							still_unique |= comp->flag == cmp_equal && is_unique(le) && is_unique(re); /* unique if only equi-joins on unique columns are there */
 							if (is_full(rel->op) || (is_left(rel->op) && found_left) || (is_right(rel->op) && found_right)) /* on outer joins, min and max cannot be propagated on some cases */
 								continue;

sql/test/miscellaneous/Tests/unique_keys.test

@@ -91,7 +91,7 @@ project (
 | | | | table("sys"."testkeys") [ "testkeys"."a" NOT NULL UNIQUE HASHCOL , "testkeys"."b" UNIQUE HASHCOL  ]
 | | | ) [ ("testkeys"."b" UNIQUE HASHCOL ) = (int(32) "1") ],
 | | | table("sys"."othertable") [ "othertable"."a" UNIQUE ]
-| | ) [ ("testkeys"."a" NOT NULL UNIQUE HASHCOL ) = ("othertable"."a" NOT NULL UNIQUE) ]
+| | ) [ ("testkeys"."a" NOT NULL UNIQUE HASHCOL ) = ("othertable"."a" UNIQUE) ]
 | ) [ (int(32) "2") <= ("othertable"."a" UNIQUE) <= (int(32) "5") ]
 ) [ "testkeys"."a" NOT NULL UNIQUE HASHCOL  ]