MDEV-8795 Equal expression propagation does not work for temporal literals

mysql-test/r/type_date.result

@@ -748,5 +748,16 @@ Note	1003	select `test`.`t1`.`a` AS `a` from `test`.`t1` where ((`test`.`t1`.`a`
 DROP TABLE t1;
 SET timestamp=DEFAULT;
 #
+# MDEV-8795 Equal expression propagation does not work for temporal literals
+#
+CREATE TABLE t1 (a DATE);
+INSERT INTO t1 VALUES ('2001-01-01'),('2001-01-02');
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE COALESCE(a)=DATE'2001-01-01' AND COALESCE(a)>=DATE'2001-01-01';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where
+Warnings:
+Note	1003	select `test`.`t1`.`a` AS `a` from `test`.`t1` where (coalesce(`test`.`t1`.`a`) = DATE'2001-01-01')
+DROP TABLE t1;
+#
 # End of 10.1 tests
 #

mysql-test/r/type_datetime.result

@@ -1085,5 +1085,16 @@ Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a` from `test`.`t1` where ((`test`.`t1`.`a` = TIME'00:00:00') and (<cache>(length(TIMESTAMP'2001-01-01 00:00:00')) = (40 + rand())))
 DROP TABLE t1;
 #
+# MDEV-8795 Equal expression propagation does not work for temporal literals
+#
+CREATE TABLE t1 (a DATETIME);
+INSERT INTO t1 VALUES ('2001-01-01 00:00:00'),('2001-01-02 00:00:00');
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE COALESCE(a)=TIMESTAMP'2001-01-01 00:00:00' AND COALESCE(a)>=TIMESTAMP'2001-01-01 00:00:00';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where
+Warnings:
+Note	1003	select `test`.`t1`.`a` AS `a` from `test`.`t1` where (coalesce(`test`.`t1`.`a`) = TIMESTAMP'2001-01-01 00:00:00')
+DROP TABLE t1;
+#
 # End of 10.1 tests
 #

mysql-test/r/type_time.result

@@ -958,5 +958,16 @@ Note	1003	select `test`.`t1`.`a` AS `a` from `test`.`t1` where ((`test`.`t1`.`a`
 DROP TABLE t1;
 SET timestamp=DEFAULT;
 #
+# MDEV-8795 Equal expression propagation does not work for temporal literals
+#
+CREATE TABLE t1 (a TIME);
+INSERT INTO t1 VALUES ('00:00:01'),('00:00:02');
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE COALESCE(a)=TIME'00:00:01' AND COALESCE(a)>=TIME'00:00:01';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where
+Warnings:
+Note	1003	select `test`.`t1`.`a` AS `a` from `test`.`t1` where (coalesce(`test`.`t1`.`a`) = TIME'00:00:01')
+DROP TABLE t1;
+#
 # End of 10.1 tests
 #

mysql-test/t/type_date.test

@@ -531,6 +531,15 @@ DROP TABLE t1;
 
 SET timestamp=DEFAULT;
 
+--echo #
+--echo # MDEV-8795 Equal expression propagation does not work for temporal literals
+--echo #
+CREATE TABLE t1 (a DATE);
+INSERT INTO t1 VALUES ('2001-01-01'),('2001-01-02');
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE COALESCE(a)=DATE'2001-01-01' AND COALESCE(a)>=DATE'2001-01-01';
+DROP TABLE t1;
+
+
 --echo #
 --echo # End of 10.1 tests
 --echo #

mysql-test/t/type_datetime.test

@@ -655,6 +655,14 @@ SET sql_mode=DEFAULT;
 --let $TYPE= DATETIME
 --source include/equal_fields_propagation_datetime.inc
 
+--echo #
+--echo # MDEV-8795 Equal expression propagation does not work for temporal literals
+--echo #
+CREATE TABLE t1 (a DATETIME);
+INSERT INTO t1 VALUES ('2001-01-01 00:00:00'),('2001-01-02 00:00:00');
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE COALESCE(a)=TIMESTAMP'2001-01-01 00:00:00' AND COALESCE(a)>=TIMESTAMP'2001-01-01 00:00:00';
+DROP TABLE t1;
+
 --echo #
 --echo # End of 10.1 tests
 --echo #

mysql-test/t/type_time.test

@@ -576,6 +576,14 @@ DROP TABLE t1;
 
 SET timestamp=DEFAULT;
 
+--echo #
+--echo # MDEV-8795 Equal expression propagation does not work for temporal literals
+--echo #
+CREATE TABLE t1 (a TIME);
+INSERT INTO t1 VALUES ('00:00:01'),('00:00:02');
+EXPLAIN EXTENDED SELECT * FROM t1 WHERE COALESCE(a)=TIME'00:00:01' AND COALESCE(a)>=TIME'00:00:01';
+DROP TABLE t1;
+
 --echo #
 --echo # End of 10.1 tests
 --echo #

sql/item.cc

@@ -6430,6 +6430,12 @@ void Item_date_literal::print(String *str, enum_query_type query_type)
 }
 
 
+Item *Item_date_literal::clone_item(THD *thd)
+{
+  return new (thd->mem_root) Item_date_literal(thd, &cached_time);
+}
+
+
 bool Item_date_literal::get_date(MYSQL_TIME *ltime, ulonglong fuzzy_date)
 {
   DBUG_ASSERT(fixed);
@@ -6450,6 +6456,12 @@ void Item_datetime_literal::print(String *str, enum_query_type query_type)
 }
 
 
+Item *Item_datetime_literal::clone_item(THD *thd)
+{
+  return new (thd->mem_root) Item_datetime_literal(thd, &cached_time, decimals);
+}
+
+
 bool Item_datetime_literal::get_date(MYSQL_TIME *ltime, ulonglong fuzzy_date)
 {
   DBUG_ASSERT(fixed);
@@ -6470,6 +6482,12 @@ void Item_time_literal::print(String *str, enum_query_type query_type)
 }
 
 
+Item *Item_time_literal::clone_item(THD *thd)
+{
+  return new (thd->mem_root) Item_time_literal(thd, &cached_time, decimals);
+}
+
+
 bool Item_time_literal::get_date(MYSQL_TIME *ltime, ulonglong fuzzy_date)
 {
   DBUG_ASSERT(fixed);

sql/item.h

@@ -3348,6 +3348,7 @@ class Item_date_literal: public Item_temporal_literal
   }
   enum_field_types field_type() const { return MYSQL_TYPE_DATE; }
   void print(String *str, enum_query_type query_type);
+  Item *clone_item(THD *thd);
   bool get_date(MYSQL_TIME *res, ulonglong fuzzy_date);
 };
 
@@ -3366,6 +3367,7 @@ class Item_time_literal: public Item_temporal_literal
   }
   enum_field_types field_type() const { return MYSQL_TYPE_TIME; }
   void print(String *str, enum_query_type query_type);
+  Item *clone_item(THD *thd);
   bool get_date(MYSQL_TIME *res, ulonglong fuzzy_date);
 };
 
@@ -3386,6 +3388,7 @@ class Item_datetime_literal: public Item_temporal_literal
   }
   enum_field_types field_type() const { return MYSQL_TYPE_DATETIME; }
   void print(String *str, enum_query_type query_type);
+  Item *clone_item(THD *thd);
   bool get_date(MYSQL_TIME *res, ulonglong fuzzy_date);
 };