MDEV-8860 Wrong result for WHERE 2016 < SOME (SELECT CAST(time_column AS DATETIME) FROM t1)

MDEV-8875 Wrong metadata for MAX(CAST(time_column AS DATETIME))

Author: Alexander Barkov

mysql-test/r/func_time.result

@@ -1726,7 +1726,7 @@ select 1 from t1 where 1 < some (select cast(a as datetime) from t1);
 1
 1
 Warnings:
-Warning	1292Truncated incorrect DOUBLE value: '2001-01-01 00:01:00'
+Warning	1292Incorrect datetime value: '1'
 drop table t1;
 SET timestamp=DEFAULT;
 select time('10:10:10') > 10;

mysql-test/r/type_datetime.result

@@ -1096,5 +1096,48 @@ 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;
 #
+# MDEV-8875 Wrong metadata for MAX(CAST(time_column AS DATETIME))
+#
+SET timestamp=UNIX_TIMESTAMP('2015-01-01 00:00:00');
+CREATE TABLE t1 (a TIME);
+INSERT INTO t1 VALUES ('00:00:00'),('00:01:00');
+SELECT MAX(CAST(a AS DATETIME)) FROM t1;
+Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
+def	MAX(CAST(a AS DATETIME))	12	19	19	Y	128	0	63
+MAX(CAST(a AS DATETIME))
+2015-01-01 00:01:00
+CREATE TABLE t2 AS SELECT MAX(CAST(a AS DATETIME)) FROM t1;
+SHOW CREATE TABLE t2;
+Table	Create Table
+t2	CREATE TABLE `t2` (
+ `MAX(CAST(a AS DATETIME))` datetime DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+DROP TABLE t2;
+DROP TABLE t1;
+SET timestamp=DEFAULT;
+#
+# MDEV-8860 Wrong result for WHERE 2016 < SOME (SELECT CAST(time_column AS DATETIME) FROM t1)
+#
+SET timestamp=UNIX_TIMESTAMP('2015-01-01 00:00:00');
+CREATE TABLE t1 (a TIME);
+INSERT INTO t1 VALUES ('00:00:00'),('00:01:00');
+SELECT 1 FROM t1 WHERE 2016 > SOME (SELECT CAST(a AS DATETIME) FROM t1);
+1
+Warnings:
+Warning	1292	Incorrect datetime value: '2016'
+SELECT * FROM t1 WHERE 2016 > CAST(a AS DATETIME);
+a
+Warnings:
+Warning	1292	Incorrect datetime value: '2016'
+SELECT 1 FROM t1 WHERE 20160101 > SOME (SELECT CAST(a AS DATETIME) FROM t1);
+1
+1
+1
+SELECT * FROM t1 WHERE 20160101 > CAST(a AS DATETIME);
+a
+00:00:00
+00:01:00
+DROP TABLE t1;
+#
 # End of 10.1 tests
 #

mysql-test/t/type_datetime.test

@@ -663,6 +663,35 @@ 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 # MDEV-8875 Wrong metadata for MAX(CAST(time_column AS DATETIME))
+--echo #
+SET timestamp=UNIX_TIMESTAMP('2015-01-01 00:00:00');
+CREATE TABLE t1 (a TIME);
+INSERT INTO t1 VALUES ('00:00:00'),('00:01:00');
+--disable_ps_protocol
+--enable_metadata
+SELECT MAX(CAST(a AS DATETIME)) FROM t1;
+--disable_metadata
+--enable_ps_protocol
+CREATE TABLE t2 AS SELECT MAX(CAST(a AS DATETIME)) FROM t1;
+SHOW CREATE TABLE t2;
+DROP TABLE t2;
+DROP TABLE t1;
+SET timestamp=DEFAULT;
+
+--echo #
+--echo # MDEV-8860 Wrong result for WHERE 2016 < SOME (SELECT CAST(time_column AS DATETIME) FROM t1)
+--echo #
+SET timestamp=UNIX_TIMESTAMP('2015-01-01 00:00:00');
+CREATE TABLE t1 (a TIME);
+INSERT INTO t1 VALUES ('00:00:00'),('00:01:00');
+SELECT 1 FROM t1 WHERE 2016 > SOME (SELECT CAST(a AS DATETIME) FROM t1);
+SELECT * FROM t1 WHERE 2016 > CAST(a AS DATETIME);
+SELECT 1 FROM t1 WHERE 20160101 > SOME (SELECT CAST(a AS DATETIME) FROM t1);
+SELECT * FROM t1 WHERE 20160101 > CAST(a AS DATETIME);
+DROP TABLE t1;
+
 --echo #
 --echo # End of 10.1 tests
 --echo #

sql/item_sum.cc

@@ -1190,7 +1190,15 @@ Item_sum_hybrid::fix_fields(THD *thd, Item **ref)
  decimals=item->decimals;
  with_subselect= args[0]->with_subselect;
 
- switch (hybrid_type= item->result_type()) {
+ Item *item2= item->real_item();
+ if (item2->type() == Item::FIELD_ITEM)
+ set_handler_by_field_type(((Item_field*) item2)->field->type());
+ else if (item->cmp_type() == TIME_RESULT)
+ set_handler_by_field_type(item2->field_type());
+ else
+ set_handler_by_result_type(item2->result_type());
+
+ switch (Item_sum_hybrid::result_type()) {
  case INT_RESULT:
  case DECIMAL_RESULT:
  case STRING_RESULT:
@@ -1210,11 +1218,6 @@ Item_sum_hybrid::fix_fields(THD *thd, Item **ref)
  result_field=0;
  null_value=1;
  fix_length_and_dec();
- item= item->real_item();
- if (item->type() == Item::FIELD_ITEM)
- hybrid_field_type= ((Item_field*) item)->field->type();
- else
- hybrid_field_type= Item::field_type();
 
  if (check_sum_func(thd, ref))
  return TRUE;
@@ -2235,7 +2238,7 @@ void Item_sum_num::reset_field()
 
 void Item_sum_hybrid::reset_field()
 {
- switch(hybrid_type) {
+ switch(Item_sum_hybrid::result_type()) {
  case STRING_RESULT:
  {
  char buff[MAX_FIELD_WIDTH];
@@ -2507,7 +2510,7 @@ Item *Item_sum_avg::result_item(THD *thd, Field *field)
 
 void Item_sum_hybrid::update_field()
 {
- switch (hybrid_type) {
+ switch (Item_sum_hybrid::result_type()) {
  case STRING_RESULT:
  min_max_update_str_field();
  break;

sql/item_sum.h

@@ -1027,26 +1027,26 @@ class Item_sum_std :public Item_sum_variance
 // This class is a string or number function depending on num_func
 class Arg_comparator;
 class Item_cache;
-class Item_sum_hybrid :public Item_sum
+class Item_sum_hybrid :public Item_sum, public Type_handler_hybrid_field_type
 {
 protected:
  Item_cache *value, *arg_cache;
  Arg_comparator *cmp;
- Item_result hybrid_type;
- enum_field_types hybrid_field_type;
  int cmp_sign;
  bool was_values; // Set if we have found at least one row (for max/min only)
  bool was_null_value;
 
  public:
  Item_sum_hybrid(THD *thd, Item *item_par,int sign):
- Item_sum(thd, item_par), value(0), arg_cache(0), cmp(0),
- hybrid_type(INT_RESULT), hybrid_field_type(MYSQL_TYPE_LONGLONG),
+ Item_sum(thd, item_par),
+ Type_handler_hybrid_field_type(MYSQL_TYPE_LONGLONG),
+ value(0), arg_cache(0), cmp(0),
  cmp_sign(sign), was_values(TRUE)
  { collation.set(&my_charset_bin); }
  Item_sum_hybrid(THD *thd, Item_sum_hybrid *item)
- :Item_sum(thd, item), value(item->value), arg_cache(0),
- hybrid_type(item->hybrid_type), hybrid_field_type(item->hybrid_field_type),
+ :Item_sum(thd, item),
+ Type_handler_hybrid_field_type(item),
+ value(item->value), arg_cache(0),
  cmp_sign(item->cmp_sign), was_values(item->was_values)
  { }
  bool fix_fields(THD *, Item **);
@@ -1058,8 +1058,12 @@ class Item_sum_hybrid :public Item_sum
  void reset_field();
  String *val_str(String *);
  bool keep_field_type(void) const { return 1; }
- enum Item_result result_type () const { return hybrid_type; }
- enum enum_field_types field_type() const { return hybrid_field_type; }
+ enum Item_result result_type () const
+ { return Type_handler_hybrid_field_type::result_type(); }
+ enum Item_result cmp_type () const
+ { return Type_handler_hybrid_field_type::cmp_type(); }
+ enum enum_field_types field_type() const
+ { return Type_handler_hybrid_field_type::field_type(); }
  void update_field();
  void min_max_update_str_field();
  void min_max_update_real_field();

sql/sql_type.h

@@ -270,6 +270,12 @@ class Type_handler_hybrid_field_type: public Type_handler
  const Type_handler *get_handler_by_field_type(enum_field_types type) const;
 public:
  Type_handler_hybrid_field_type();
+ Type_handler_hybrid_field_type(enum_field_types type)
+ :m_type_handler(get_handler_by_field_type(type))
+ { }
+ Type_handler_hybrid_field_type(const Type_handler_hybrid_field_type *other)
+ :m_type_handler(other->m_type_handler)
+ { }
  enum_field_types field_type() const { return m_type_handler->field_type(); }
  Item_result result_type() const { return m_type_handler->result_type(); }
  Item_result cmp_type() const { return m_type_handler->cmp_type(); }