MDEV-21319 COUNT(*) returns 1, actual SELECT returns no result in 10.3.21, but 1 result in 10.1.41

Item_ref::val_(datetime|time)_packed() erroneously called
(*ref)->val_(datetime|time)_packed().

- Fixing to call (*ref)->val_(datetime|time)_packed_result().
- Backporting Item::val_(datetime|time)_packed_result() from 10.3.
- Fixing Item_field::get_date_result() to handle null_value in the same
  way how Item_field::get_date() does.

mysql-test/r/type_datetime.result

@@ -1198,5 +1198,86 @@ Warning	1292	Incorrect datetime value: '2' for column 'pk' at row 2
 DROP VIEW v1;
 DROP TABLE t1;
 #
+# MDEV-21319 COUNT(*) returns 1, actual SELECT returns no result in 10.3.21, but 1 result in 10.1.41
+#
+CREATE TABLE t1
+(
+id INT NOT NULL PRIMARY KEY,
+id2 INT,
+k TINYINT,
+j INT,
+t DATETIME,
+KEY k1 (id2,k,j,t)
+);
+INSERT INTO t1 VALUES
+(53,54,1,0,'2019-12-13 10:09:59'),
+(54,54,1,0,'2019-12-13 16:28:41'),
+(55,54,1,0,'2019-12-13 16:29:10'),
+(56,54,1,0,'2019-12-13 16:29:43'),
+(57,54,1,0,'2019-12-13 16:30:16'),
+(58,54,1,0,'2019-12-13 16:30:49'),
+(59,54,1,0,'2019-12-13 16:31:23'),
+(60,54,1,0,'2019-12-13 16:31:55'),
+(61,54,1,0,'2019-12-13 16:32:28'),
+(62,54,1,0,'2019-12-13 16:33:01'),
+(63,54,1,0,'2019-12-13 16:33:34'),
+(64,54,1,0,'2019-12-13 16:34:07'),
+(65,54,1,0,'2019-12-13 16:34:40'),
+(66,54,1,0,'2019-12-13 16:35:13'),
+(67,54,1,0,'2019-12-13 16:35:46'),
+(68,54,1,0,'2019-12-13 16:36:19');
+SELECT t FROM t1 GROUP BY t HAVING t=max(t);
+t
+2019-12-13 10:09:59
+2019-12-13 16:28:41
+2019-12-13 16:29:10
+2019-12-13 16:29:43
+2019-12-13 16:30:16
+2019-12-13 16:30:49
+2019-12-13 16:31:23
+2019-12-13 16:31:55
+2019-12-13 16:32:28
+2019-12-13 16:33:01
+2019-12-13 16:33:34
+2019-12-13 16:34:07
+2019-12-13 16:34:40
+2019-12-13 16:35:13
+2019-12-13 16:35:46
+2019-12-13 16:36:19
+SELECT t FROM t1 WHERE id2=54 and j=0 and k=1 GROUP BY t HAVING t=max(t);
+t
+2019-12-13 10:09:59
+2019-12-13 16:28:41
+2019-12-13 16:29:10
+2019-12-13 16:29:43
+2019-12-13 16:30:16
+2019-12-13 16:30:49
+2019-12-13 16:31:23
+2019-12-13 16:31:55
+2019-12-13 16:32:28
+2019-12-13 16:33:01
+2019-12-13 16:33:34
+2019-12-13 16:34:07
+2019-12-13 16:34:40
+2019-12-13 16:35:13
+2019-12-13 16:35:46
+2019-12-13 16:36:19
+DROP TABLE t1;
+CREATE TABLE t1 (pk INT);
+CREATE VIEW v1 AS SELECT * FROM t1;
+INSERT INTO t1 VALUES (1);
+SELECT pk<DATE'2001-01-01' FROM t1 GROUP BY pk;
+pk<DATE'2001-01-01'
+1
+Warnings:
+Warning	1292	Incorrect datetime value: '1' for column 'pk' at row 1
+SELECT pk<DATE'2001-01-01' FROM v1 GROUP BY pk;
+pk<DATE'2001-01-01'
+1
+Warnings:
+Warning	1292	Incorrect datetime value: '1' for column 'pk' at row 1
+DROP VIEW v1;
+DROP TABLE t1;
+#
 # End of 10.1 tests
 #

mysql-test/r/type_time.result

@@ -1246,5 +1246,71 @@ drop table t1;
 SET @@optimizer_use_condition_selectivity= @save_optimizer_use_condition_selectivity;
 set @@old_mode= @save_old_mode;
 #
+# MDEV-21319 COUNT(*) returns 1, actual SELECT returns no result in 10.3.21, but 1 result in 10.1.41
+#
+CREATE OR REPLACE TABLE t1
+(
+id INT NOT NULL PRIMARY KEY,
+id2 INT,
+k TINYINT,
+j INT,
+t TIME,
+KEY k1 (id2,k,j,t)
+);
+INSERT INTO t1 VALUES
+(53,54,1,0,'10:09:59'),
+(54,54,1,0,'16:28:41'),
+(55,54,1,0,'16:29:10'),
+(56,54,1,0,'16:29:43'),
+(57,54,1,0,'16:30:16'),
+(58,54,1,0,'16:30:49'),
+(59,54,1,0,'16:31:23'),
+(60,54,1,0,'16:31:55'),
+(61,54,1,0,'16:32:28'),
+(62,54,1,0,'16:33:01'),
+(63,54,1,0,'16:33:34'),
+(64,54,1,0,'16:34:07'),
+(65,54,1,0,'16:34:40'),
+(66,54,1,0,'16:35:13'),
+(67,54,1,0,'16:35:46'),
+(68,54,1,0,'16:36:19');
+SELECT t FROM t1 GROUP BY t HAVING t=MAX(t);
+t
+10:09:59
+16:28:41
+16:29:10
+16:29:43
+16:30:16
+16:30:49
+16:31:23
+16:31:55
+16:32:28
+16:33:01
+16:33:34
+16:34:07
+16:34:40
+16:35:13
+16:35:46
+16:36:19
+SELECT t FROM t1 WHERE id2=54 AND j=0 AND k=1 GROUP BY t HAVING t=MAX(t);
+t
+10:09:59
+16:28:41
+16:29:10
+16:29:43
+16:30:16
+16:30:49
+16:31:23
+16:31:55
+16:32:28
+16:33:01
+16:33:34
+16:34:07
+16:34:40
+16:35:13
+16:35:46
+16:36:19
+DROP TABLE t1;
+#
 # End of 10.1 tests
 #

mysql-test/t/type_datetime.test

@@ -747,6 +747,49 @@ DROP VIEW v1;
 DROP TABLE t1;
 
 
+--echo #
+--echo # MDEV-21319 COUNT(*) returns 1, actual SELECT returns no result in 10.3.21, but 1 result in 10.1.41
+--echo #
+
+CREATE TABLE t1
+(
+  id INT NOT NULL PRIMARY KEY,
+  id2 INT,
+  k TINYINT,
+  j INT,
+  t DATETIME,
+  KEY k1 (id2,k,j,t)
+);
+INSERT INTO t1 VALUES
+(53,54,1,0,'2019-12-13 10:09:59'),
+(54,54,1,0,'2019-12-13 16:28:41'),
+(55,54,1,0,'2019-12-13 16:29:10'),
+(56,54,1,0,'2019-12-13 16:29:43'),
+(57,54,1,0,'2019-12-13 16:30:16'),
+(58,54,1,0,'2019-12-13 16:30:49'),
+(59,54,1,0,'2019-12-13 16:31:23'),
+(60,54,1,0,'2019-12-13 16:31:55'),
+(61,54,1,0,'2019-12-13 16:32:28'),
+(62,54,1,0,'2019-12-13 16:33:01'),
+(63,54,1,0,'2019-12-13 16:33:34'),
+(64,54,1,0,'2019-12-13 16:34:07'),
+(65,54,1,0,'2019-12-13 16:34:40'),
+(66,54,1,0,'2019-12-13 16:35:13'),
+(67,54,1,0,'2019-12-13 16:35:46'),
+(68,54,1,0,'2019-12-13 16:36:19');
+SELECT t FROM t1 GROUP BY t HAVING t=max(t);
+SELECT t FROM t1 WHERE id2=54 and j=0 and k=1 GROUP BY t HAVING t=max(t);
+DROP TABLE t1;
+
+CREATE TABLE t1 (pk INT);
+CREATE VIEW v1 AS SELECT * FROM t1;
+INSERT INTO t1 VALUES (1);
+SELECT pk<DATE'2001-01-01' FROM t1 GROUP BY pk;
+SELECT pk<DATE'2001-01-01' FROM v1 GROUP BY pk;
+DROP VIEW v1;
+DROP TABLE t1;
+
+
 --echo #
 --echo # End of 10.1 tests
 --echo #

mysql-test/t/type_time.test

@@ -746,6 +746,40 @@ drop table t1;
 SET @@optimizer_use_condition_selectivity= @save_optimizer_use_condition_selectivity;
 set @@old_mode= @save_old_mode;
 
+--echo #
+--echo # MDEV-21319 COUNT(*) returns 1, actual SELECT returns no result in 10.3.21, but 1 result in 10.1.41
+--echo #
+
+CREATE OR REPLACE TABLE t1
+(
+  id INT NOT NULL PRIMARY KEY,
+  id2 INT,
+  k TINYINT,
+  j INT,
+  t TIME,
+  KEY k1 (id2,k,j,t)
+);
+INSERT INTO t1 VALUES
+(53,54,1,0,'10:09:59'),
+(54,54,1,0,'16:28:41'),
+(55,54,1,0,'16:29:10'),
+(56,54,1,0,'16:29:43'),
+(57,54,1,0,'16:30:16'),
+(58,54,1,0,'16:30:49'),
+(59,54,1,0,'16:31:23'),
+(60,54,1,0,'16:31:55'),
+(61,54,1,0,'16:32:28'),
+(62,54,1,0,'16:33:01'),
+(63,54,1,0,'16:33:34'),
+(64,54,1,0,'16:34:07'),
+(65,54,1,0,'16:34:40'),
+(66,54,1,0,'16:35:13'),
+(67,54,1,0,'16:35:46'),
+(68,54,1,0,'16:36:19');
+SELECT t FROM t1 GROUP BY t HAVING t=MAX(t);
+SELECT t FROM t1 WHERE id2=54 AND j=0 AND k=1 GROUP BY t HAVING t=MAX(t);
+DROP TABLE t1;
+
 --echo #
 --echo # End of 10.1 tests
 --echo #

sql/item.cc

@@ -145,6 +145,19 @@ bool Item::get_date_with_conversion(MYSQL_TIME *ltime, ulonglong fuzzydate)
 }
 
 
+longlong Item::val_datetime_packed_result()
+{
+  MYSQL_TIME ltime, tmp;
+  if (get_date_result(&ltime, TIME_FUZZY_DATES | TIME_INVALID_DATES))
+    return 0;
+  if (ltime.time_type != MYSQL_TIMESTAMP_TIME)
+    return pack_time(&ltime);
+  if ((null_value= time_to_datetime_with_warn(current_thd, &ltime, &tmp, 0)))
+    return 0;
+  return pack_time(&tmp);
+}
+
+
 /**
   Get date/time/datetime.
   If DATETIME or DATE result is returned, it's converted to TIME.
@@ -2594,12 +2607,13 @@ bool Item_field::get_date(MYSQL_TIME *ltime,ulonglong fuzzydate)
 
 bool Item_field::get_date_result(MYSQL_TIME *ltime, ulonglong fuzzydate)
 {
-  if (result_field->is_null() || result_field->get_date(ltime,fuzzydate))
+  if ((null_value= result_field->is_null()) ||
+      result_field->get_date(ltime, fuzzydate))
   {
     bzero((char*) ltime,sizeof(*ltime));
-    return (null_value= 1);
+    return true;
   }
-  return (null_value= 0);
+  return false;
 }
 
 
@@ -7313,7 +7327,7 @@ bool Item_ref::get_date(MYSQL_TIME *ltime,ulonglong fuzzydate)
 longlong Item_ref::val_datetime_packed()
 {
   DBUG_ASSERT(fixed);
-  longlong tmp= (*ref)->val_datetime_packed();
+  longlong tmp= (*ref)->val_datetime_packed_result();
   null_value= (*ref)->null_value;
   return tmp;
 }
@@ -7322,7 +7336,7 @@ longlong Item_ref::val_datetime_packed()
 longlong Item_ref::val_time_packed()
 {
   DBUG_ASSERT(fixed);
-  longlong tmp= (*ref)->val_time_packed();
+  longlong tmp= (*ref)->val_time_packed_result();
   null_value= (*ref)->null_value;
   return tmp;
 }

sql/item.h

@@ -1302,6 +1302,13 @@ class Item: public Value_source,
     uint fuzzydate= TIME_FUZZY_DATES | TIME_INVALID_DATES | TIME_TIME_ONLY;
     return get_date(&ltime, fuzzydate) ? 0 : pack_time(&ltime);
   }
+  longlong val_datetime_packed_result();
+  longlong val_time_packed_result()
+  {
+    MYSQL_TIME ltime;
+    uint fuzzydate= TIME_TIME_ONLY | TIME_INVALID_DATES | TIME_FUZZY_DATES;
+    return get_date_result(&ltime, fuzzydate) ? 0 : pack_time(&ltime);
+  }
   // Get a temporal value in packed DATE/DATETIME or TIME format
   longlong val_temporal_packed(enum_field_types f_type)
   {