Code that had to be changed so that CREATE ... SELECT ... always

creates proper column types, out of any function, expression or from
other tables.

mysql-test/r/create.result

@@ -76,4 +76,14 @@ x	varchar(50)	YES		NULL
 describe t2;
 Field	Type	Null	Key	Default	Extra
 x	char(50)	YES		NULL	
+drop table t2;
+create table t2 select now() as a , curtime() as b, curdate() as c , 1+1 as d , 1.0 + 1 as e , 33333333333333333 + 3 as f;
+describe t2;
+Field	Type	Null	Key	Default	Extra
+a	datetime			0000-00-00 00:00:00	
+b	time			00:00:00	
+c	date			0000-00-00	
+d	bigint(17)			0	
+e	double(18,1)			0.0	
+f	bigint(17)			0	
 drop table t1,t2;

sql/field.h

@@ -593,6 +593,10 @@ public:
     :Field_str(ptr_arg, 10, null_ptr_arg, null_bit_arg,
 	       unireg_check_arg, field_name_arg, table_arg)
     {}
+  Field_date(bool maybe_null_arg, const char *field_name_arg,
+		 struct st_table *table_arg)
+    :Field_str((char*) 0,10, maybe_null_arg ? (uchar*) "": 0,0,
+	       NONE, field_name_arg, table_arg) {}
   enum_field_types type() const { return FIELD_TYPE_DATE;}
   enum ha_base_keytype key_type() const { return HA_KEYTYPE_ULONG_INT; }
   enum Item_result cmp_type () const { return INT_RESULT; }
@@ -650,6 +654,10 @@ public:
     :Field_str(ptr_arg, 8, null_ptr_arg, null_bit_arg,
 	       unireg_check_arg, field_name_arg, table_arg)
     {}
+  Field_time(bool maybe_null_arg, const char *field_name_arg,
+		 struct st_table *table_arg)
+    :Field_str((char*) 0,8, maybe_null_arg ? (uchar*) "": 0,0,
+	       NONE, field_name_arg, table_arg) {}
   enum_field_types type() const { return FIELD_TYPE_TIME;}
   enum ha_base_keytype key_type() const { return HA_KEYTYPE_INT24; }
   enum Item_result cmp_type () const { return INT_RESULT; }
@@ -678,6 +686,10 @@ public:
     :Field_str(ptr_arg, 19, null_ptr_arg, null_bit_arg,
 	       unireg_check_arg, field_name_arg, table_arg)
     {}
+  Field_datetime(bool maybe_null_arg, const char *field_name_arg,
+		 struct st_table *table_arg)
+    :Field_str((char*) 0,19, maybe_null_arg ? (uchar*) "": 0,0,
+	       NONE, field_name_arg, table_arg) {}
   enum_field_types type() const { return FIELD_TYPE_DATETIME;}
 #ifdef HAVE_LONG_LONG
   enum ha_base_keytype key_type() const { return HA_KEYTYPE_ULONGLONG; }

sql/item.h

@@ -64,7 +64,7 @@ public:
   virtual longlong val_int()=0;
   virtual String *val_str(String*)=0;
   virtual void make_field(Send_field *field)=0;
-  virtual Field *tmp_table_field() { return 0; }
+  virtual Field *tmp_table_field(TABLE *t_arg=(TABLE *)0) { return 0; }
   virtual const char *full_name() const { return name ? name : "???"; }
   virtual double  val_result() { return val(); }
   virtual longlong val_int_result() { return val_int(); }
@@ -128,7 +128,7 @@ public:
   {
     return field->result_type();
   }
-  Field *tmp_table_field() { return result_field; }
+  Field *tmp_table_field(TABLE *t_arg=(TABLE *)0) { return result_field; }
   bool get_date(TIME *ltime,bool fuzzydate);  
   bool get_time(TIME *ltime);  
   bool is_null() { return field->is_null(); }
@@ -308,7 +308,7 @@ public:
   Field *result_field;				/* Save result here */
   Item_result_field() :result_field(0) {}
   ~Item_result_field() {}			/* Required with gcc 2.95 */
-  Field *tmp_table_field() { return result_field; }
+  Field *tmp_table_field(TABLE *t_arg=(TABLE *)0) { return result_field; }
   table_map used_tables() const { return 1; }
   virtual void fix_length_and_dec()=0;
 };

sql/item_func.h

@@ -135,6 +135,11 @@ public:
   longlong val_int() { return (longlong) val(); }
   enum Item_result result_type () const { return REAL_RESULT; }
   void fix_length_and_dec() { decimals=NOT_FIXED_DEC; max_length=float_length(decimals); }
+  Field *tmp_table_field(TABLE *t_arg)
+  {
+    if (!t_arg) return result_field;
+    return new Field_double(max_length, maybe_null, name,t_arg,decimals);
+  }  
 };
 
 class Item_num_func :public Item_func
@@ -164,6 +169,11 @@ class Item_num_op :public Item_func
   void fix_length_and_dec() { fix_num_length_and_dec(); find_num_type(); }
   void find_num_type(void);
   bool is_null() { (void) val(); return null_value; }
+  Field *tmp_table_field(TABLE *t_arg)
+  {
+    if (!t_arg) return result_field;
+    return args[0]->result_type() == INT_RESULT ? ((max_length > 11) ?  (Field *)new Field_longlong(max_length,maybe_null,name, t_arg,unsigned_flag) :  (Field *)new Field_long(max_length,maybe_null,name, t_arg,unsigned_flag))  : (Field *) new Field_double(max_length, maybe_null, name,t_arg,decimals);
+  }  
 };
 
 
@@ -179,6 +189,11 @@ public:
   String *val_str(String*str);
   enum Item_result result_type () const { return INT_RESULT; }
   void fix_length_and_dec() { decimals=0; max_length=21; }
+  Field *tmp_table_field(TABLE *t_arg)
+  {
+    if (!t_arg) return result_field;
+    return (max_length > 11) ?  (Field *)new Field_longlong(max_length,maybe_null,name, t_arg,unsigned_flag) :  (Field *)new Field_long(max_length,maybe_null,name, t_arg,unsigned_flag);
+  }  
 };
 
 class Item_func_plus :public Item_num_op

sql/item_strfunc.h

@@ -35,6 +35,11 @@ public:
   double val();
   enum Item_result result_type () const { return STRING_RESULT; }
   void left_right_max_length();
+  Field *tmp_table_field(TABLE *t_arg)
+  {
+    if (!t_arg) return result_field;
+    return (max_length > 255) ? (Field *)new Field_blob(max_length,maybe_null, name,t_arg, binary) : (Field *) new Field_string(max_length,maybe_null, name,t_arg, binary);
+  }  
 };
 
 class Item_func_md5 :public Item_str_func

sql/item_timefunc.h

@@ -233,6 +233,11 @@ public:
   {
     init_make_field(tmp_field,FIELD_TYPE_DATE);
   }
+  Field *tmp_table_field(TABLE *t_arg)
+  {
+    if (!t_arg) return result_field;
+    return new Field_date(maybe_null, name, t_arg);
+  }  
 };
 
 
@@ -246,6 +251,11 @@ public:
   {
     init_make_field(tmp_field,FIELD_TYPE_DATETIME);
   }
+  Field *tmp_table_field(TABLE *t_arg)
+  {
+    if (!t_arg) return result_field;
+    return   new Field_datetime(maybe_null, name, t_arg);
+  }  
 };
 
 
@@ -268,6 +278,11 @@ public:
   {
     init_make_field(tmp_field,FIELD_TYPE_TIME);
   }
+  Field *tmp_table_field(TABLE *t_arg)
+  {
+    if (!t_arg) return result_field;
+    return   new Field_time(maybe_null, name, t_arg);
+  }  
 };
 
 
@@ -355,6 +370,12 @@ public:
   {
     init_make_field(tmp_field,FIELD_TYPE_TIME);
   }
+  Field *tmp_table_field(TABLE *t_arg)
+  {
+    if (!t_arg) return result_field;
+    return   new Field_time(maybe_null, name, t_arg);
+  }  
+
 };
 
 enum interval_type { INTERVAL_YEAR, INTERVAL_MONTH, INTERVAL_DAY,

sql/sql_table.cc

@@ -704,8 +704,11 @@ TABLE *create_table_from_items(THD *thd, HA_CREATE_INFO *create_info,
       my_error(ER_WRONG_COLUMN_NAME,MYF(0),item->name);
       DBUG_RETURN(0);
     }
-
-    Field *field=create_tmp_field(thd, &tmp_table, item, item->type(),
+    Field *field;
+    if (item->type() == Item::FUNC_ITEM)
+      field=item->tmp_table_field(&tmp_table);
+    else
+      field=create_tmp_field(thd, &tmp_table, item, item->type(),
 				  (Item_result_field***) 0, &tmp_field,0,0);
     if (!field ||
 	!(cr_field=new create_field(field,(item->type() == Item::FIELD_ITEM ?