MDEV-12719 Determine Item::result_type() from Item::type_handler()

15 files changed, 28 insertions, 168 deletions

diff --git a/sql/item.cc b/sql/item.cc
index c3ecf7d8597..e775862ca3a 100644
--- a/sql/item.cc
+++ b/sql/item.cc
@@ -9840,7 +9840,7 @@ Item_type_holder::Item_type_holder(THD *thd, Item *item)
   DBUG_ASSERT(item->fixed);
   maybe_null= item->maybe_null;
   get_full_info(item);
-  DBUG_ASSERT(!decimals || Item_type_holder::result_type() != INT_RESULT);
+  DBUG_ASSERT(!decimals || result_type() != INT_RESULT);
   prev_decimal_int_part= item->decimal_int_part();
 }
 
@@ -9889,14 +9889,14 @@ bool Item_type_holder::join_types(THD *thd, Item *item)
     which is on the right side of the UNION, the data type handler
     changes to type_handler_longlong, while decimals is still NOT_FIXED_DEC.
   */
-  if (Item_type_holder::result_type() == INT_RESULT)
+  if (result_type() == INT_RESULT)
     decimals= 0;
   else
     decimals= MY_MAX(decimals, item->decimals);
 
   Type_geometry_attributes::join(item);
 
-  if (Item_type_holder::result_type() == DECIMAL_RESULT)
+  if (result_type() == DECIMAL_RESULT)
   {
     decimals= MY_MIN(MY_MAX(decimals, item->decimals), DECIMAL_MAX_SCALE);
     int item_int_part= item->decimal_int_part();
@@ -9908,7 +9908,7 @@ bool Item_type_holder::join_types(THD *thd, Item *item)
                                                              unsigned_flag);
   }
 
-  switch (Item_type_holder::result_type())
+  switch (result_type())
   {
   case STRING_RESULT:
   {
diff --git a/sql/item.h b/sql/item.h
index 2b25df5520e..ad34320c560 100644
--- a/sql/item.h
+++ b/sql/item.h
@@ -746,7 +746,7 @@ public:
     return type_handler();
   }
   /* result_type() of an item specifies how the value should be returned */
-  virtual Item_result result_type() const
+  Item_result result_type() const
   {
     return type_handler()->result_type();
   }
@@ -2230,8 +2230,6 @@ public:
   inline enum Type type() const;
   const Type_handler *type_handler() const
   { return Type_handler_hybrid_field_type::type_handler(); }
-  enum Item_result result_type () const
-  { return Type_handler_hybrid_field_type::result_type(); }
   uint cols() const { return this_item()->cols(); }
   Item* element_index(uint i) { return this_item()->element_index(i); }
   Item** addr(uint i) { return this_item()->addr(i); }
@@ -2389,7 +2387,6 @@ public:
   Item **this_item_addr(THD *thd, Item **);
 
   inline enum Type type() const;
-  inline Item_result result_type() const;
   const Type_handler *type_handler() const { return this_item()->type_handler(); }
 
 public:
@@ -2414,12 +2411,6 @@ inline enum Item::Type Item_case_expr::type() const
   return this_item()->type();
 }
 
-inline Item_result Item_case_expr::result_type() const
-{
-  return this_item()->result_type();
-}
-
-
 /*
   NAME_CONST(given_name, const_value). 
   This 'function' has all properties of the supplied const_value (which is 
@@ -2457,11 +2448,6 @@ public:
     return value_item->type_handler();
   }
 
-  Item_result result_type() const
-  {
-    return value_item->result_type();
-  }
-
   bool const_item() const
   {
     return TRUE;
@@ -2683,10 +2669,6 @@ public:
     const Type_handler *handler= field->type_handler();
     return handler->type_handler_for_item_field();
   }
-  enum Item_result result_type () const
-  {
-    return field->result_type();
-  }
   const Type_handler *cast_to_int_type_handler() const
   {
     return field->type_handler()->cast_to_int_type_handler();
@@ -2830,7 +2812,6 @@ public:
   { return get_item_copy<Item_field_row>(thd, mem_root, this); }
 
   const Type_handler *type_handler() const { return &type_handler_row; }
-  Item_result result_type() const{ return ROW_RESULT ; }
   uint cols() const { return arg_count; }
   bool element_index_by_name(uint *idx, const LEX_CSTRING &name) const;
   Item* element_index(uint i) { return arg_count ? args[i] : this; }
@@ -2909,7 +2890,6 @@ public:
   int save_in_field(Field *field, bool no_conversions);
   int save_safe_in_field(Field *field);
   bool send(Protocol *protocol, st_value *buffer);
-  enum Item_result result_type () const { return STRING_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_null; }
   bool basic_const_item() const { return 1; }
   Item *clone_item(THD *thd);
@@ -3089,8 +3069,6 @@ public:
 
   const Type_handler *type_handler() const
   { return Type_handler_hybrid_field_type::type_handler(); }
-  enum Item_result result_type () const
-  { return Type_handler_hybrid_field_type::result_type(); }
 
   Item_param(THD *thd, const LEX_CSTRING *name_arg,
              uint pos_in_query_arg, uint len_in_query_arg);
@@ -3225,7 +3203,6 @@ public:
     }
   Item_int(THD *thd, const char *str_arg, uint length=64);
   enum Type type() const { return INT_ITEM; }
-  enum Item_result result_type () const { return INT_RESULT; }
   const Type_handler *type_handler() const
   {
     // The same condition is repeated in Item::create_tmp_field()
@@ -3317,7 +3294,6 @@ public:
   Item_decimal(THD *thd, const uchar *bin, int precision, int scale);
 
   enum Type type() const { return DECIMAL_ITEM; }
-  enum Item_result result_type () const { return DECIMAL_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_newdecimal; }
   longlong val_int();
   double val_real();
@@ -3498,7 +3474,6 @@ public:
   }
   my_decimal *val_decimal(my_decimal *);
   int save_in_field(Field *field, bool no_conversions);
-  enum Item_result result_type () const { return STRING_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_varchar; }
   bool basic_const_item() const { return 1; }
   bool eq(const Item *item, bool binary_cmp) const
@@ -3770,7 +3745,6 @@ public:
     hex_string_init(thd, str, str_length);
   }
   enum Type type() const { return VARBIN_ITEM; }
-  enum Item_result result_type () const { return STRING_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_varchar; }
   virtual Item *safe_charset_converter(THD *thd, CHARSET_INFO *tocs)
   {
@@ -3907,7 +3881,6 @@ public:
   bool const_item() const { return true; }
   enum Type type() const { return DATE_ITEM; }
   bool eq(const Item *item, bool binary_cmp) const;
-  enum Item_result result_type () const { return STRING_RESULT; }
 
   bool check_partition_func_processor(void *int_arg) {return FALSE;}
 
@@ -4305,7 +4278,6 @@ public:
   void save_org_in_field(Field *field, fast_field_copier optimizer_data);
   fast_field_copier setup_fast_field_copier(Field *field)
   { return (*ref)->setup_fast_field_copier(field); }
-  enum Item_result result_type () const { return (*ref)->result_type(); }
   const Type_handler *type_handler() const { return (*ref)->type_handler(); }
   const Type_handler *real_type_handler() const
   { return (*ref)->real_type_handler(); }
@@ -4603,7 +4575,6 @@ public:
   }
   int save_in_field(Field *to, bool no_conversions);
   const Type_handler *type_handler() const { return orig_item->type_handler(); }
-  enum Item_result result_type () const { return orig_item->result_type(); }
   table_map used_tables() const { return orig_item->used_tables(); }
   void update_used_tables()
   {
@@ -5023,8 +4994,6 @@ public:
 
   const Type_handler *type_handler() const
   { return Type_handler_hybrid_field_type::type_handler(); }
-  enum Item_result result_type () const
-  { return Type_handler_hybrid_field_type::result_type(); }
 
   void make_field(THD *thd, Send_field *field) { item->make_field(thd, field); }
   table_map used_tables() const { return (table_map) 1L; }
@@ -5551,8 +5520,6 @@ public:
 
   const Type_handler *type_handler() const
   { return Type_handler_hybrid_field_type::type_handler(); }
-  enum Item_result result_type () const
-  { return Type_handler_hybrid_field_type::result_type(); }
 
   virtual void keep_array() {}
   virtual void print(String *str, enum_query_type query_type);
@@ -5653,7 +5620,6 @@ public:
   longlong val_int();
   String* val_str(String *str);
   my_decimal *val_decimal(my_decimal *);
-  enum Item_result result_type() const { return INT_RESULT; }
   bool cache_value();
   int save_in_field(Field *field, bool no_conversions);
   Item *convert_to_basic_const_item(THD *thd);
@@ -5699,7 +5665,6 @@ public:
   longlong val_int();
   String* val_str(String *str);
   my_decimal *val_decimal(my_decimal *);
-  enum Item_result result_type() const { return REAL_RESULT; }
   bool cache_value();
   Item *convert_to_basic_const_item(THD *thd);
   Item *get_copy(THD *thd, MEM_ROOT *mem_root)
@@ -5718,7 +5683,6 @@ public:
   longlong val_int();
   String* val_str(String *str);
   my_decimal *val_decimal(my_decimal *);
-  enum Item_result result_type() const { return DECIMAL_RESULT; }
   bool cache_value();
   Item *convert_to_basic_const_item(THD *thd);
   Item *get_copy(THD *thd, MEM_ROOT *mem_root)
@@ -5745,7 +5709,6 @@ public:
   longlong val_int();
   String* val_str(String *);
   my_decimal *val_decimal(my_decimal *);
-  enum Item_result result_type() const { return STRING_RESULT; }
   CHARSET_INFO *charset() const { return value->charset(); };
   int save_in_field(Field *field, bool no_conversions);
   bool cache_value();
@@ -5827,8 +5790,6 @@ public:
     return 0;
   };
 
-  enum Item_result result_type() const { return ROW_RESULT; }
-  
   uint cols() const { return item_count; }
   Item *element_index(uint i) { return values[i]; }
   Item **addr(uint i) { return (Item **) (values + i); }
@@ -5878,22 +5839,6 @@ public:
     const Type_handler *handler= Type_handler_hybrid_field_type::type_handler();
     return handler->type_handler_for_item_field();
   }
-  enum Item_result result_type () const
-  {
-    /*
-      In 10.1 Item_type_holder::result_type() returned
-      Field::result_merge_type(field_type()), which returned STRING_RESULT
-      for the BIT data type. In 10.2 it returns INT_RESULT, similar
-      to what Field_bit::result_type() does. This should not be
-      important because Item_type_holder is a limited purpose Item
-      and its result_type() should not be called from outside of
-      Item_type_holder. It's called only internally from decimal_int_part()
-      from join_types(), to calculate "decimals" of the result data type.
-      As soon as we get BIT as one of the joined types, the result field
-      type cannot be numeric: it's either BIT, or VARBINARY.
-    */
-    return Type_handler_hybrid_field_type::result_type();
-  }
   const Type_handler *real_type_handler() const
   {
     return Type_handler_hybrid_field_type::type_handler();
diff --git a/sql/item_func.cc b/sql/item_func.cc
index c961264e9fd..8df5c301f3a 100644
--- a/sql/item_func.cc
+++ b/sql/item_func.cc
@@ -4745,7 +4745,7 @@ Item_func_set_user_var::check(bool use_result_field)
   if (use_result_field && !result_field)
     use_result_field= FALSE;
 
-  switch (Item_func_set_user_var::result_type()) {
+  switch (result_type()) {
   case REAL_RESULT:
   {
     save_result.vreal= use_result_field ? result_field->val_real() :
@@ -4838,7 +4838,7 @@ Item_func_set_user_var::update()
   bool res= 0;
   DBUG_ENTER("Item_func_set_user_var::update");
 
-  switch (Item_func_set_user_var::result_type()) {
+  switch (result_type()) {
   case REAL_RESULT:
   {
     res= update_hash((void*) &save_result.vreal,sizeof(save_result.vreal),
@@ -5308,7 +5308,7 @@ void Item_func_get_user_var::fix_length_and_dec()
     max_length= m_var_entry->length;
     collation.set(m_var_entry->charset(), DERIVATION_IMPLICIT);
     set_handler_by_result_type(m_var_entry->type);
-    switch (Item_func_get_user_var::result_type()) {
+    switch (result_type()) {
     case REAL_RESULT:
       fix_char_length(DBL_DIG + 8);
       break;
@@ -5585,32 +5585,6 @@ bool Item_func_get_system_var::check_vcol_func_processor(void *arg)
   return mark_unsupported_function("@@", var->name.str, arg, VCOL_SESSION_FUNC);
 }
 
-enum Item_result Item_func_get_system_var::result_type() const
-{
-  switch (var->show_type())
-  {
-    case SHOW_BOOL:
-    case SHOW_MY_BOOL:
-    case SHOW_SINT:
-    case SHOW_SLONG:
-    case SHOW_SLONGLONG:
-    case SHOW_UINT:
-    case SHOW_ULONG:
-    case SHOW_ULONGLONG:
-    case SHOW_HA_ROWS:
-      return INT_RESULT;
-    case SHOW_CHAR: 
-    case SHOW_CHAR_PTR: 
-    case SHOW_LEX_STRING:
-      return STRING_RESULT;
-    case SHOW_DOUBLE:
-      return REAL_RESULT;
-    default:
-      my_error(ER_VAR_CANT_BE_READ, MYF(0), var->name.str);
-      return STRING_RESULT;                   // keep the compiler happy
-  }
-}
-
 
 const Type_handler *Item_func_get_system_var::type_handler() const
 {
@@ -6453,20 +6427,13 @@ Item_func_sp::make_field(THD *thd, Send_field *tmp_field)
 const Type_handler *Item_func_sp::type_handler() const
 {
   DBUG_ENTER("Item_func_sp::type_handler");
+  DBUG_PRINT("info", ("m_sp = %p", (void *) m_sp));
   DBUG_ASSERT(sp_result_field);
   // This converts ENUM/SET to STRING
   const Type_handler *handler= sp_result_field->type_handler();
   DBUG_RETURN(handler->type_handler_for_item_field());
 }
 
-Item_result
-Item_func_sp::result_type() const
-{
-  DBUG_ENTER("Item_func_sp::result_type");
-  DBUG_PRINT("info", ("m_sp = %p", (void *) m_sp));
-  DBUG_ASSERT(sp_result_field);
-  DBUG_RETURN(sp_result_field->result_type());
-}
 
 longlong Item_func_found_rows::val_int()
 {
diff --git a/sql/item_func.h b/sql/item_func.h
index 02b2244cc55..74c986545cd 100644
--- a/sql/item_func.h
+++ b/sql/item_func.h
@@ -370,7 +370,6 @@ public:
   my_decimal *val_decimal(my_decimal *decimal_value);
   longlong val_int()
     { DBUG_ASSERT(fixed == 1); return (longlong) rint(val_real()); }
-  enum Item_result result_type () const { return REAL_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_double; }
   void fix_length_and_dec()
   { decimals= NOT_FIXED_DEC; max_length= float_length(decimals); }
@@ -397,8 +396,6 @@ public:
     :Item_func(thd, item), Type_handler_hybrid_field_type(item) { }
   const Type_handler *type_handler() const
   { return Type_handler_hybrid_field_type::type_handler(); }
-  enum Item_result result_type () const
-  { return Type_handler_hybrid_field_type::result_type(); }
   Field::geometry_type get_geometry_type() const
   { return Type_geometry_attributes::get_geometry_type(); };
 };
@@ -731,7 +728,6 @@ public:
   { collation.set_numeric(); }
   double val_real();
   String *val_str(String*str);
-  enum Item_result result_type () const { return INT_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_longlong; }
   void fix_length_and_dec() {}
 };
@@ -903,7 +899,6 @@ public:
   double val_real();
   longlong val_int();
   my_decimal *val_decimal(my_decimal*);
-  enum Item_result result_type () const { return DECIMAL_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_newdecimal; }
   void fix_length_and_dec_generic() {}
   void fix_length_and_dec()
@@ -1539,7 +1534,6 @@ public:
   my_decimal *val_decimal(my_decimal *dec) { return args[0]->val_decimal(dec); }
   const char *func_name() const { return "rollup_const"; }
   bool const_item() const { return 0; }
-  Item_result result_type() const { return args[0]->result_type(); }
   const Type_handler *type_handler() const { return args[0]->type_handler(); }
   void fix_length_and_dec()
   {
@@ -1913,7 +1907,6 @@ public:
     }
   }
   void cleanup();
-  Item_result result_type () const { return udf.result_type(); }
   table_map not_null_tables() const { return 0; }
   bool is_expensive() { return 1; }
   virtual void print(String *str, enum_query_type query_type);
@@ -1965,7 +1958,6 @@ public:
   longlong val_int();
   double val_real() { return (double) Item_func_udf_int::val_int(); }
   String *val_str(String *str);
-  enum Item_result result_type () const { return INT_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_longlong; }
   void fix_length_and_dec() { decimals= 0; max_length= 21; }
   Item *get_copy(THD *thd, MEM_ROOT *mem_root)
@@ -1984,7 +1976,6 @@ public:
   double val_real();
   my_decimal *val_decimal(my_decimal *);
   String *val_str(String *str);
-  enum Item_result result_type () const { return DECIMAL_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_newdecimal; }
   void fix_length_and_dec() { fix_num_length_and_dec(); }
   Item *get_copy(THD *thd, MEM_ROOT *mem_root)
@@ -2024,7 +2015,6 @@ public:
     string2my_decimal(E_DEC_FATAL_ERROR, res, dec_buf);
     return dec_buf;
   }
-  enum Item_result result_type () const { return STRING_RESULT; }
   const Type_handler *type_handler() const { return string_type_handler(); }
   void fix_length_and_dec();
   Item *get_copy(THD *thd, MEM_ROOT *mem_root)
@@ -2077,7 +2067,6 @@ public:
     { DBUG_ASSERT(fixed == 1); null_value=1; return 0; }
   double val_real() { DBUG_ASSERT(fixed == 1); null_value= 1; return 0.0; }
   longlong val_int() { DBUG_ASSERT(fixed == 1); null_value=1; return 0; }
-  enum Item_result result_type () const { return STRING_RESULT; }
   void fix_length_and_dec() { maybe_null=1; max_length=0; }
 };
 
@@ -2390,7 +2379,6 @@ public:
   void print(String *str, enum_query_type query_type);
   bool const_item() const { return true; }
   table_map used_tables() const { return 0; }
-  enum Item_result result_type() const;
   const Type_handler *type_handler() const;
   double val_real();
   longlong val_int();
@@ -2661,8 +2649,6 @@ public:
   }
   void make_field(THD *thd, Send_field *tmp_field);
 
-  Item_result result_type() const;
-
   longlong val_int()
   {
     if (execute())
@@ -2834,7 +2820,6 @@ public:
   String *val_str(String *);
   my_decimal *val_decimal(my_decimal *);
   void fix_length_and_dec();
-  enum Item_result result_type () const { return last_value->result_type(); }
   const char *func_name() const { return "last_value"; }
   table_map not_null_tables() const { return 0; }
   const Type_handler *type_handler() const { return last_value->type_handler(); }
diff --git a/sql/item_row.h b/sql/item_row.h
index 375321e4755..83ceb80a359 100644
--- a/sql/item_row.h
+++ b/sql/item_row.h
@@ -90,7 +90,6 @@ public:
                       List<Item> &fields, uint flags);
   table_map used_tables() const { return used_tables_cache; };
   bool const_item() const { return const_item_cache; };
-  enum Item_result result_type() const { return ROW_RESULT; }
   void update_used_tables()
   {
     used_tables_and_const_cache_init();
diff --git a/sql/item_strfunc.h b/sql/item_strfunc.h
index 664b5bf2455..267408187f3 100644
--- a/sql/item_strfunc.h
+++ b/sql/item_strfunc.h
@@ -64,7 +64,6 @@ public:
   longlong val_int();
   double val_real();
   my_decimal *val_decimal(my_decimal *);
-  enum Item_result result_type () const { return STRING_RESULT; }
   const Type_handler *type_handler() const { return string_type_handler(); }
   void left_right_max_length();
   bool fix_fields(THD *thd, Item **ref);
diff --git a/sql/item_subselect.cc b/sql/item_subselect.cc
index 4dc2546866c..09fbf3e239c 100644
--- a/sql/item_subselect.cc
+++ b/sql/item_subselect.cc
@@ -1172,11 +1172,6 @@ void Item_singlerow_subselect::store(uint i, Item *item)
   row[i]->cache_value();
 }
 
-enum Item_result Item_singlerow_subselect::result_type() const
-{
-  return engine->result_type();
-}
-
 const Type_handler *Item_singlerow_subselect::type_handler() const
 {
   return engine->type_handler();
diff --git a/sql/item_subselect.h b/sql/item_subselect.h
index ff6293e6e5c..5d9e2e7c0cd 100644
--- a/sql/item_subselect.h
+++ b/sql/item_subselect.h
@@ -303,7 +303,6 @@ public:
   my_decimal *val_decimal(my_decimal *);
   bool val_bool();
   bool get_date(MYSQL_TIME *ltime, ulonglong fuzzydate);
-  enum Item_result result_type() const;
   const Type_handler *type_handler() const;
   void fix_length_and_dec();
 
@@ -394,7 +393,6 @@ public:
   }
   void no_rows_in_result();
 
-  enum Item_result result_type() const { return INT_RESULT;}
   const Type_handler *type_handler() const { return &type_handler_longlong; }
   longlong val_int();
   double val_real();
diff --git a/sql/item_sum.cc b/sql/item_sum.cc
index 6d510253259..6dccd67316f 100644
--- a/sql/item_sum.cc
+++ b/sql/item_sum.cc
@@ -1229,7 +1229,7 @@ Item_sum_sum::Item_sum_sum(THD *thd, Item_sum_sum *item)
    count(item->count)
 {
   /* TODO: check if the following assignments are really needed */
-  if (Item_sum_sum::result_type() == DECIMAL_RESULT)
+  if (result_type() == DECIMAL_RESULT)
   {
     my_decimal2decimal(item->dec_buffs, dec_buffs);
     my_decimal2decimal(item->dec_buffs + 1, dec_buffs + 1);
@@ -1249,7 +1249,7 @@ void Item_sum_sum::clear()
   DBUG_ENTER("Item_sum_sum::clear");
   null_value=1;
   count= 0;
-  if (Item_sum_sum::result_type() == DECIMAL_RESULT)
+  if (result_type() == DECIMAL_RESULT)
   {
     curr_dec_buff= 0;
     my_decimal_set_zero(dec_buffs);
@@ -1304,7 +1304,7 @@ void Item_sum_sum::add_helper(bool perform_removal)
 {
   DBUG_ENTER("Item_sum_sum::add_helper");
 
-  if (Item_sum_sum::result_type() == DECIMAL_RESULT)
+  if (result_type() == DECIMAL_RESULT)
   {
     my_decimal value;
     const my_decimal *val= aggr->arg_val_decimal(&value);
@@ -1361,7 +1361,7 @@ longlong Item_sum_sum::val_int()
   DBUG_ASSERT(fixed == 1);
   if (aggr)
     aggr->endup();
-  if (Item_sum_sum::result_type() == DECIMAL_RESULT)
+  if (result_type() == DECIMAL_RESULT)
   {
     longlong result;
     my_decimal2int(E_DEC_FATAL_ERROR, dec_buffs + curr_dec_buff, unsigned_flag,
@@ -1377,7 +1377,7 @@ double Item_sum_sum::val_real()
   DBUG_ASSERT(fixed == 1);
   if (aggr)
     aggr->endup();
-  if (Item_sum_sum::result_type() == DECIMAL_RESULT)
+  if (result_type() == DECIMAL_RESULT)
     my_decimal2double(E_DEC_FATAL_ERROR, dec_buffs + curr_dec_buff, &sum);
   return sum;
 }
@@ -1387,7 +1387,7 @@ String *Item_sum_sum::val_str(String *str)
 {
   if (aggr)
     aggr->endup();
-  if (Item_sum_sum::result_type() == DECIMAL_RESULT)
+  if (result_type() == DECIMAL_RESULT)
     return val_string_from_decimal(str);
   return val_string_from_real(str);
 }
@@ -1397,7 +1397,7 @@ my_decimal *Item_sum_sum::val_decimal(my_decimal *val)
 {
   if (aggr)
     aggr->endup();
-  if (Item_sum_sum::result_type() == DECIMAL_RESULT)
+  if (result_type() == DECIMAL_RESULT)
     return null_value ? NULL : (dec_buffs + curr_dec_buff);
   return val_decimal_from_real(val);
 }
@@ -1642,7 +1642,7 @@ Field *Item_sum_avg::create_tmp_field(bool group, TABLE *table)
       and unpack on access.
     */
     Field *field= new (table->in_use->mem_root)
-      Field_string(((Item_sum_avg::result_type() == DECIMAL_RESULT) ?
+      Field_string(((result_type() == DECIMAL_RESULT) ?
                    dec_bin_size : sizeof(double)) + sizeof(longlong),
                    0, &name, &my_charset_bin);
     if (field)
@@ -1710,7 +1710,7 @@ my_decimal *Item_sum_avg::val_decimal(my_decimal *val)
     For non-DECIMAL result_type() the division will be done in
     Item_sum_avg::val_real().
   */
-  if (Item_sum_avg::result_type() != DECIMAL_RESULT)
+  if (result_type() != DECIMAL_RESULT)
     return val_decimal_from_real(val);
 
   sum_dec= dec_buffs + curr_dec_buff;
@@ -1724,7 +1724,7 @@ String *Item_sum_avg::val_str(String *str)
 {
   if (aggr)
     aggr->endup();
-  if (Item_sum_avg::result_type() == DECIMAL_RESULT)
+  if (result_type() == DECIMAL_RESULT)
     return val_string_from_decimal(str);
   return val_string_from_real(str);
 }
@@ -2307,7 +2307,7 @@ void Item_sum_num::reset_field()
 
 void Item_sum_hybrid::reset_field()
 {
-  switch(Item_sum_hybrid::result_type()) {
+  switch(result_type()) {
   case STRING_RESULT:
   {
     char buff[MAX_FIELD_WIDTH];
@@ -2390,7 +2390,7 @@ void Item_sum_hybrid::reset_field()
 void Item_sum_sum::reset_field()
 {
   DBUG_ASSERT (aggr->Aggrtype() != Aggregator::DISTINCT_AGGREGATOR);
-  if (Item_sum_sum::result_type() == DECIMAL_RESULT)
+  if (result_type() == DECIMAL_RESULT)
   {
     my_decimal value, *arg_val= args[0]->val_decimal(&value);
     if (!arg_val)                               // Null
@@ -2426,7 +2426,7 @@ void Item_sum_avg::reset_field()
 {
   uchar *res=result_field->ptr;
   DBUG_ASSERT (aggr->Aggrtype() != Aggregator::DISTINCT_AGGREGATOR);
-  if (Item_sum_avg::result_type() == DECIMAL_RESULT)
+  if (result_type() == DECIMAL_RESULT)
   {
     longlong tmp;
     my_decimal value, *arg_dec= args[0]->val_decimal(&value);
@@ -2484,7 +2484,7 @@ void Item_sum_bit::update_field()
 void Item_sum_sum::update_field()
 {
   DBUG_ASSERT (aggr->Aggrtype() != Aggregator::DISTINCT_AGGREGATOR);
-  if (Item_sum_sum::result_type() == DECIMAL_RESULT)
+  if (result_type() == DECIMAL_RESULT)
   {
     my_decimal value, *arg_val= args[0]->val_decimal(&value);
     if (!args[0]->null_value)
@@ -2539,7 +2539,7 @@ void Item_sum_avg::update_field()
 
   DBUG_ASSERT (aggr->Aggrtype() != Aggregator::DISTINCT_AGGREGATOR);
 
-  if (Item_sum_avg::result_type() == DECIMAL_RESULT)
+  if (result_type() == DECIMAL_RESULT)
   {
     my_decimal value, *arg_val= args[0]->val_decimal(&value);
     if (!args[0]->null_value)
@@ -2578,7 +2578,7 @@ void Item_sum_avg::update_field()
 Item *Item_sum_avg::result_item(THD *thd, Field *field)
 {
   return
-    Item_sum_avg::result_type() == DECIMAL_RESULT ?
+    result_type() == DECIMAL_RESULT ?
     (Item_avg_field*) new (thd->mem_root) Item_avg_field_decimal(thd, this) :
     (Item_avg_field*) new (thd->mem_root) Item_avg_field_double(thd, this);
 }
@@ -2586,7 +2586,7 @@ Item *Item_sum_avg::result_item(THD *thd, Field *field)
 
 void Item_sum_hybrid::update_field()
 {
-  switch (Item_sum_hybrid::result_type()) {
+  switch (result_type()) {
   case STRING_RESULT:
     min_max_update_str_field();
     break;
diff --git a/sql/item_sum.h b/sql/item_sum.h
index 86ef54d8486..dee480ccf0a 100644
--- a/sql/item_sum.h
+++ b/sql/item_sum.h
@@ -748,7 +748,6 @@ public:
   double val_real() { DBUG_ASSERT(fixed == 1); return (double) val_int(); }
   String *val_str(String*str);
   my_decimal *val_decimal(my_decimal *);
-  enum Item_result result_type () const { return INT_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_longlong; }
   void fix_length_and_dec()
   { decimals=0; max_length=21; maybe_null=null_value=0; }
@@ -783,8 +782,6 @@ public:
   my_decimal *val_decimal(my_decimal *);
   const Type_handler *type_handler() const
   { return Type_handler_hybrid_field_type::type_handler(); }
-  enum Item_result result_type () const
-  { return Type_handler_hybrid_field_type::result_type(); }
   void fix_length_and_dec_double();
   void fix_length_and_dec_decimal();
   void reset_field();
@@ -976,7 +973,6 @@ public:
     { return sample ? "var_samp(" : "variance("; }
   Item *copy_or_same(THD* thd);
   Field *create_tmp_field(bool group, TABLE *table);
-  enum Item_result result_type () const { return REAL_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_double; }
   void cleanup()
   {
@@ -1048,8 +1044,6 @@ protected:
   }
   const Type_handler *type_handler() const
   { return Type_handler_hybrid_field_type::type_handler(); }
-  enum Item_result result_type () const
-  { return Type_handler_hybrid_field_type::result_type(); }
   void update_field();
   void min_max_update_str_field();
   void min_max_update_real_field();
@@ -1255,7 +1249,6 @@ public:
   Item_avg_field_double(THD *thd, Item_sum_avg *item)
    :Item_avg_field(thd, item)
   { }
-  enum Item_result result_type () const { return REAL_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_double; }
   longlong val_int() { return val_int_from_real(); }
   my_decimal *val_decimal(my_decimal *dec) { return val_decimal_from_real(dec); }
@@ -1276,7 +1269,6 @@ public:
     f_scale(item->f_scale),
     dec_bin_size(item->dec_bin_size)
   { }
-  enum Item_result result_type () const { return DECIMAL_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_newdecimal; }
   double val_real() { return val_real_from_decimal(); }
   longlong val_int() { return val_int_from_decimal(); }
@@ -1303,7 +1295,6 @@ public:
   { return val_decimal_from_real(dec_buf); }
   bool is_null() { update_null_value(); return null_value; }
   const Type_handler *type_handler() const { return &type_handler_double; }
-  enum Item_result result_type () const { return REAL_RESULT; }
   Item *get_copy(THD *thd, MEM_ROOT *mem_root)
   { return get_item_copy<Item_variance_field>(thd, mem_root, this); }
 };
@@ -1401,7 +1392,6 @@ class Item_sum_udf_float :public Item_udf_sum
   double val_real();
   String *val_str(String*str);
   my_decimal *val_decimal(my_decimal *);
-  enum Item_result result_type () const { return REAL_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_double; }
   void fix_length_and_dec() { fix_num_length_and_dec(); }
   Item *copy_or_same(THD* thd);
@@ -1424,7 +1414,6 @@ public:
     { DBUG_ASSERT(fixed == 1); return (double) Item_sum_udf_int::val_int(); }
   String *val_str(String*str);
   my_decimal *val_decimal(my_decimal *);
-  enum Item_result result_type () const { return INT_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_longlong; }
   void fix_length_and_dec() { decimals=0; max_length=21; }
   Item *copy_or_same(THD* thd);
@@ -1466,7 +1455,6 @@ public:
     return cs->cset->strtoll10(cs, res->ptr(), &end, &err_not_used);
   }
   my_decimal *val_decimal(my_decimal *dec);
-  enum Item_result result_type () const { return STRING_RESULT; }
   const Type_handler *type_handler() const { return string_type_handler(); }
   void fix_length_and_dec();
   Item *copy_or_same(THD* thd);
@@ -1488,7 +1476,6 @@ public:
   double val_real();
   longlong val_int();
   my_decimal *val_decimal(my_decimal *);
-  enum Item_result result_type () const { return DECIMAL_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_newdecimal; }
   void fix_length_and_dec() { fix_num_length_and_dec(); }
   Item *copy_or_same(THD* thd);
@@ -1564,7 +1551,6 @@ public:
     { DBUG_ASSERT(fixed == 1); null_value=1; return 0; }
   double val_real() { DBUG_ASSERT(fixed == 1); null_value=1; return 0.0; }
   longlong val_int() { DBUG_ASSERT(fixed == 1); null_value=1; return 0; }
-  enum Item_result result_type () const { return STRING_RESULT; }
   void fix_length_and_dec() { maybe_null=1; max_length=0; }
   enum Sumfunctype sum_func () const { return UDF_SUM_FUNC; }
   void clear() {}
@@ -1638,7 +1624,6 @@ public:
 
   enum Sumfunctype sum_func () const {return GROUP_CONCAT_FUNC;}
   const char *func_name() const { return "group_concat("; }
-  virtual Item_result result_type () const { return STRING_RESULT; }
   const Type_handler *type_handler() const
   {
     if (too_big_for_varchar())
diff --git a/sql/item_timefunc.h b/sql/item_timefunc.h
index a9a7706ceea..ced4bf4b31e 100644
--- a/sql/item_timefunc.h
+++ b/sql/item_timefunc.h
@@ -155,7 +155,6 @@ public:
     return str;
   }
   const char *func_name() const { return "month"; }
-  enum Item_result result_type () const { return INT_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_longlong; }
   void fix_length_and_dec()
   { 
@@ -405,7 +404,6 @@ public:
   {
      return (odbc_type ? "dayofweek" : "weekday");
   }
-  enum Item_result result_type () const { return INT_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_longlong; }
   void fix_length_and_dec()
   {
@@ -430,7 +428,6 @@ class Item_func_dayname :public Item_func_weekday
   Item_func_dayname(THD *thd, Item *a): Item_func_weekday(thd, a, 0) {}
   const char *func_name() const { return "dayname"; }
   String *val_str(String *str);
-  enum Item_result result_type () const { return STRING_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_varchar; }
   void fix_length_and_dec();
   bool check_partition_func_processor(void *int_arg) {return TRUE;}
@@ -527,7 +524,6 @@ public:
   Item_temporal_func(THD *thd, Item *a): Item_func(thd, a) {}
   Item_temporal_func(THD *thd, Item *a, Item *b): Item_func(thd, a, b) {}
   Item_temporal_func(THD *thd, Item *a, Item *b, Item *c): Item_func(thd, a, b, c) {}
-  enum Item_result result_type () const { return STRING_RESULT; }
   String *val_str(String *str);
   longlong val_int() { return val_int_from_date(); }
   double val_real() { return val_real_from_date(); }
diff --git a/sql/item_windowfunc.cc b/sql/item_windowfunc.cc
index 7117ac69548..6ab903a81bb 100644
--- a/sql/item_windowfunc.cc
+++ b/sql/item_windowfunc.cc
@@ -250,7 +250,7 @@ bool Item_sum_hybrid_simple::fix_fields(THD *thd, Item **ref)
     set_handler_by_result_type(item2->result_type(),
                                max_length, collation.collation);
 
-  switch (Item_sum_hybrid_simple::result_type()) {
+  switch (result_type()) {
   case INT_RESULT:
   case DECIMAL_RESULT:
   case STRING_RESULT:
@@ -352,7 +352,7 @@ Field *Item_sum_hybrid_simple::create_tmp_field(bool group, TABLE *table)
 
 void Item_sum_hybrid_simple::reset_field()
 {
-  switch(Item_sum_hybrid_simple::result_type()) {
+  switch(result_type()) {
   case STRING_RESULT:
   {
     char buff[MAX_FIELD_WIDTH];
diff --git a/sql/item_windowfunc.h b/sql/item_windowfunc.h
index 5e3a28ffade..77cbd556e60 100644
--- a/sql/item_windowfunc.h
+++ b/sql/item_windowfunc.h
@@ -303,8 +303,6 @@ class Item_sum_hybrid_simple : public Item_sum,
   my_decimal *val_decimal(my_decimal *);
   void reset_field();
   String *val_str(String *);
-  enum Item_result result_type() const
-  { return Type_handler_hybrid_field_type::result_type(); }
   const Type_handler *type_handler() const
   { return Type_handler_hybrid_field_type::type_handler(); }
   void update_field();
@@ -509,7 +507,6 @@ class Item_sum_percent_rank: public Item_sum_window_with_row_count
     row_number= 0;
   }
   bool add();
-  enum Item_result result_type () const { return REAL_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_double; }
 
   void fix_length_and_dec()
@@ -595,7 +592,6 @@ class Item_sum_cume_dist: public Item_sum_window_with_row_count
   }
 
   void update_field() {}
-  enum Item_result result_type () const { return REAL_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_double; }
 
   void fix_length_and_dec()
@@ -672,7 +668,6 @@ class Item_sum_ntile : public Item_sum_window_with_row_count
 
   void update_field() {}
 
-  enum Item_result result_type () const { return INT_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_longlong; }
   
   Item *get_copy(THD *thd, MEM_ROOT *mem_root)
diff --git a/sql/procedure.h b/sql/procedure.h
index e3350b21369..a1c9b95f20b 100644
--- a/sql/procedure.h
+++ b/sql/procedure.h
@@ -71,7 +71,6 @@ public:
   {
      decimals=dec; max_length=float_length(dec);
   }
-  enum Item_result result_type () const { return REAL_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_double; }
   void set(double nr) { value=nr; }
   void set(longlong nr) { value=(double) nr; }
@@ -98,7 +97,6 @@ class Item_proc_int :public Item_proc
 public:
   Item_proc_int(THD *thd, const char *name_par): Item_proc(thd, name_par)
   { max_length=11; }
-  enum Item_result result_type () const { return INT_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_longlong; }
   void set(double nr) { value=(longlong) nr; }
   void set(longlong nr) { value=nr; }
@@ -117,7 +115,6 @@ class Item_proc_string :public Item_proc
 public:
   Item_proc_string(THD *thd, const char *name_par, uint length):
     Item_proc(thd, name_par) { this->max_length=length; }
-  enum Item_result result_type () const { return STRING_RESULT; }
   const Type_handler *type_handler() const { return &type_handler_varchar; }
   void set(double nr) { str_value.set_real(nr, 2, default_charset()); }
   void set(longlong nr) { str_value.set(nr, default_charset()); }
diff --git a/sql/sql_type.h b/sql/sql_type.h
index 5127ea5e796..c8b8a936355 100644
--- a/sql/sql_type.h
+++ b/sql/sql_type.h
@@ -2267,7 +2267,6 @@ public:
   {
     return m_type_handler->real_field_type();
   }
-  Item_result result_type() const { return m_type_handler->result_type(); }
   Item_result cmp_type() const { return m_type_handler->cmp_type(); }
   enum_mysql_timestamp_type mysql_timestamp_type() const
   {