MDEV-40698 ROLLUP query returns incorrect result with empty result set

mysql-test/main/mdev_40698.result

@@ -0,0 +1,55 @@
+#
+# MDEV-40698: ROLLUP query returns incorrect result with empty result set
+#
+CREATE TABLE t0(a INT, b INT, c INT);
+SELECT *, COUNT(0) FROM t0 GROUP BY a, b, c WITH ROLLUP;
+a	b	c	COUNT(0)
+NULL	NULL	NULL	0
+SELECT *, COUNT(0) FROM t0 WHERE 1=0 GROUP BY a, b, c WITH ROLLUP;
+a	b	c	COUNT(0)
+NULL	NULL	NULL	0
+SELECT *, COUNT(0), ROW_NUMBER() OVER () FROM t0 GROUP BY a, b, c WITH ROLLUP;
+a	b	c	COUNT(0)	ROW_NUMBER() OVER ()
+NULL	NULL	NULL	0	1
+INSERT INTO t0 VALUES (0, 0, 0);
+INSERT INTO t0 VALUES (0, 0, 0);
+SELECT *, COUNT(0) FROM t0 WHERE a > 0 GROUP BY a, b, c WITH ROLLUP;
+a	b	c	COUNT(0)
+NULL	NULL	NULL	0
+SELECT EXISTS (SELECT t0.a FROM t0 x WHERE 1=0 GROUP BY x.a WITH ROLLUP) AS e
+FROM t0;
+e
+1
+1
+SELECT DISTINCT a FROM t0 GROUP BY a, b WITH ROLLUP;
+a
+0
+NULL
+CREATE TABLE t1 (a INT, b INT, c INT) ENGINE=InnoDB;
+SELECT *, COUNT(0) FROM t1 GROUP BY a, b, c WITH ROLLUP;
+a	b	c	COUNT(0)
+NULL	NULL	NULL	0
+SELECT *, COUNT(0) FROM t1 WHERE 1=0 GROUP BY a, b, c WITH ROLLUP;
+a	b	c	COUNT(0)
+NULL	NULL	NULL	0
+SELECT *, COUNT(0), ROW_NUMBER() OVER () FROM t1 GROUP BY a, b, c WITH ROLLUP;
+a	b	c	COUNT(0)	ROW_NUMBER() OVER ()
+NULL	NULL	NULL	0	1
+INSERT INTO t1 VALUES (0, 0, 0);
+INSERT INTO t1 VALUES (0, 0, 0);
+SELECT *, COUNT(0) FROM t1 WHERE a > 0 GROUP BY a, b, c WITH ROLLUP;
+a	b	c	COUNT(0)
+NULL	NULL	NULL	0
+SELECT EXISTS (SELECT t1.a FROM t1 x WHERE 1=0 GROUP BY x.a WITH ROLLUP) AS e
+FROM t1;
+e
+1
+1
+SELECT DISTINCT a FROM t1 GROUP BY a, b WITH ROLLUP;
+a
+0
+NULL
+DROP TABLE t0, t1;
+#
+# End of 10.11 tests
+#

mysql-test/main/mdev_40698.test

@@ -0,0 +1,33 @@
+--source include/have_innodb.inc
+
+--echo #
+--echo # MDEV-40698: ROLLUP query returns incorrect result with empty result set
+--echo #
+
+CREATE TABLE t0(a INT, b INT, c INT);
+SELECT *, COUNT(0) FROM t0 GROUP BY a, b, c WITH ROLLUP;
+SELECT *, COUNT(0) FROM t0 WHERE 1=0 GROUP BY a, b, c WITH ROLLUP;
+SELECT *, COUNT(0), ROW_NUMBER() OVER () FROM t0 GROUP BY a, b, c WITH ROLLUP;
+INSERT INTO t0 VALUES (0, 0, 0);
+INSERT INTO t0 VALUES (0, 0, 0);
+SELECT *, COUNT(0) FROM t0 WHERE a > 0 GROUP BY a, b, c WITH ROLLUP;
+SELECT EXISTS (SELECT t0.a FROM t0 x WHERE 1=0 GROUP BY x.a WITH ROLLUP) AS e
+  FROM t0;
+SELECT DISTINCT a FROM t0 GROUP BY a, b WITH ROLLUP;
+
+CREATE TABLE t1 (a INT, b INT, c INT) ENGINE=InnoDB;
+SELECT *, COUNT(0) FROM t1 GROUP BY a, b, c WITH ROLLUP;
+SELECT *, COUNT(0) FROM t1 WHERE 1=0 GROUP BY a, b, c WITH ROLLUP;
+SELECT *, COUNT(0), ROW_NUMBER() OVER () FROM t1 GROUP BY a, b, c WITH ROLLUP;
+INSERT INTO t1 VALUES (0, 0, 0);
+INSERT INTO t1 VALUES (0, 0, 0);
+SELECT *, COUNT(0) FROM t1 WHERE a > 0 GROUP BY a, b, c WITH ROLLUP;
+SELECT EXISTS (SELECT t1.a FROM t1 x WHERE 1=0 GROUP BY x.a WITH ROLLUP) AS e
+  FROM t1;
+SELECT DISTINCT a FROM t1 GROUP BY a, b WITH ROLLUP;
+
+DROP TABLE t0, t1;
+
+--echo #
+--echo # End of 10.11 tests
+--echo #

mysql-test/main/ps_error.result

@@ -10,6 +10,7 @@ EXECUTE stmt;
 ERROR 22007: Truncated incorrect DOUBLE value: 'foo'
 SELECT a FROM t1 GROUP BY NULL WITH ROLLUP;
 a
+NULL
 DROP TABLE t1;
 SET sql_mode=DEFAULT;
 SET SQL_MODE= 'STRICT_ALL_TABLES';

mysql-test/main/win.result

@@ -3503,6 +3503,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
 select distinct 1, row_number() over (order by 1) from t1 where a=0 group by a with rollup;
 1	row_number() over (order by 1)
+1	1
 drop table t1;
 explain
 SELECT DISTINCT BIT_OR(100) OVER () FROM dual

mysql-test/suite/encryption/r/tempfiles_encrypted.result

@@ -3509,6 +3509,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
 select distinct 1, row_number() over (order by 1) from t1 where a=0 group by a with rollup;
 1	row_number() over (order by 1)
+1	1
 drop table t1;
 explain
 SELECT DISTINCT BIT_OR(100) OVER () FROM dual

sql/sql_select.cc

@@ -24496,6 +24496,7 @@ end_send_group(JOIN *join, JOIN_TAB *join_tab, bool end_of_records)
     join->fields.
   */
   List<Item> *fields= join_tab ? (join_tab-1)->fields : join->fields;
+  bool empty_set_send_rollup_total= 0;
   DBUG_ENTER("end_send_group");
 
   if (!join->items3.is_null() && !join->set_group_rpa)
@@ -24511,7 +24512,8 @@ end_send_group(JOIN *join, JOIN_TAB *join_tab, bool end_of_records)
 
     if (!join->group_sent &&
         (join->first_record ||
-         (end_of_records && !join->group && !join->group_optimized_away)))
+         join->need_empty_set_row(end_of_records,
+                                  &empty_set_send_rollup_total)))
     {
       table_map cleared_tables= (table_map) 0;
       if (join->procedure)
@@ -24567,7 +24569,8 @@ end_send_group(JOIN *join, JOIN_TAB *join_tab, bool end_of_records)
 	    join->send_records++;
             join->group_sent= true;
 	  }
-	  if (unlikely(join->rollup.state != ROLLUP::STATE_NONE && error <= 0))
+	  if (unlikely(join->rollup.state != ROLLUP::STATE_NONE &&
+      !empty_set_send_rollup_total && error <= 0))
 	  {
 	    if (join->rollup_send_data((uint) (idx+1)))
 	      error= 1;
@@ -24888,13 +24891,15 @@ end_write_group(JOIN *join, JOIN_TAB *join_tab __attribute__((unused)),
 {
   TABLE *table= join_tab->table;
   int	  idx= -1;
+  bool empty_set_send_rollup_total= 0;
   DBUG_ENTER("end_write_group");
 
   join->accepted_rows++;
   if (!join->first_record || end_of_records ||
       (idx=test_if_group_changed(join->group_fields)) >= 0)
   {
-    if (join->first_record || (end_of_records && !join->group))
+    if (join->first_record ||
+        join->need_empty_set_row(end_of_records, &empty_set_send_rollup_total))
     {
       table_map cleared_tables= (table_map) 0;
       if (join->procedure)
@@ -24919,7 +24924,8 @@ end_write_group(JOIN *join, JOIN_TAB *join_tab __attribute__((unused)),
                                                    error, 0, NULL))
 	    DBUG_RETURN(NESTED_LOOP_ERROR);
         }
-        if (unlikely(join->rollup.state != ROLLUP::STATE_NONE))
+        if (unlikely(join->rollup.state != ROLLUP::STATE_NONE &&
+                     !empty_set_send_rollup_total))
 	{
           if (unlikely(join->rollup_write_data((uint) (idx+1),
                                                join_tab->tmp_table_param,

sql/sql_select.h

@@ -1746,12 +1746,27 @@ class JOIN :public Sql_alloc
   void cleanup(bool full);
   void clear(table_map *cleared_tables);
   void inline clear_sum_funcs();
+  bool need_empty_set_row(bool end_of_records,
+                          bool *empty_set_send_rollup_total) const
+  {
+    *empty_set_send_rollup_total=
+        end_of_records && !first_record && rollup.state != ROLLUP::STATE_NONE;
+    return (end_of_records && !first_record && !group &&
+            !group_optimized_away) ||
+           *empty_set_send_rollup_total;
+  }
   bool send_row_on_empty_set()
   {
-    return (do_send_rows && implicit_grouping && !group_optimized_away &&
+    return (do_send_rows &&
+            (select_lex->olap == ROLLUP_TYPE ||
+             (implicit_grouping && !group_optimized_away)) &&
             having_value != Item::COND_FALSE);
   }
-  bool empty_result() { return (zero_result_cause && !implicit_grouping); }
+  bool empty_result()
+  {
+    return (zero_result_cause && !implicit_grouping &&
+            select_lex->olap != ROLLUP_TYPE);
+  }
   bool change_result(select_result *new_result, select_result *old_result);
   bool is_top_level_join() const
   {