Bug #27300:

  Geometry fields have a result type string and a 
  special subclass to cater for the differences
  between them and the base class (just like 
  DATE/TIME).
  When creating temporary tables for results of 
  functions that return results of type GEOMETRY
  we must construct fields of the derived class 
  instead of the base class.
  Fixed by creating a GEOMETRY field (Field_geom) 
  instead of a generic BLOB (Field_blob) in temp 
  tables for the results of GIS functions that 
  have GEOMETRY return type (Item_geometry_func).

mysql-test/r/gis.result

@@ -769,3 +769,14 @@ create table t1 (g geometry not null);
 insert into t1 values(default);
 ERROR 22003: Cannot get geometry object from data you send to the GEOMETRY field
 drop table t1;
+CREATE TABLE t1 (a GEOMETRY);
+CREATE VIEW v1 AS SELECT GeomFromwkb(ASBINARY(a)) FROM t1;
+CREATE VIEW v2 AS SELECT a FROM t1;
+DESCRIBE v1;
+Field	Type	Null	Key	Default	Extra
+GeomFromwkb(ASBINARY(a))	geometry	YES		NULL	
+DESCRIBE v2;
+Field	Type	Null	Key	Default	Extra
+a	geometry	YES		NULL	
+DROP VIEW v1,v2;
+DROP TABLE t1;

mysql-test/t/gis.test

@@ -479,3 +479,14 @@ create table t1 (g geometry not null);
 insert into t1 values(default);
 drop table t1;
 
+#
+# Bug #27300: create view with geometry functions lost columns types 
+#
+CREATE TABLE t1 (a GEOMETRY);
+CREATE VIEW v1 AS SELECT GeomFromwkb(ASBINARY(a)) FROM t1;
+CREATE VIEW v2 AS SELECT a FROM t1;
+DESCRIBE v1;
+DESCRIBE v2;
+
+DROP VIEW v1,v2;
+DROP TABLE t1;

sql/item.cc

@@ -4275,7 +4275,6 @@ Field *Item::tmp_table_field_from_field_type(TABLE *table)
   case MYSQL_TYPE_MEDIUM_BLOB:
   case MYSQL_TYPE_LONG_BLOB:
   case MYSQL_TYPE_BLOB:
-  case MYSQL_TYPE_GEOMETRY:
     if (this->type() == Item::TYPE_HOLDER)
       return new Field_blob(max_length, maybe_null, name, table,
                           collation.collation, 1);
@@ -4283,6 +4282,10 @@ Field *Item::tmp_table_field_from_field_type(TABLE *table)
       return new Field_blob(max_length, maybe_null, name, table,
                           collation.collation);
     break;					// Blob handled outside of case
+  case MYSQL_TYPE_GEOMETRY:
+    return new Field_geom(max_length, maybe_null, name, table,
+                          (Field::geometry_type)
+                          ((Item_geometry_func *)this)->get_geometry_type());
   }
 }
 

sql/sql_select.cc

@@ -8793,12 +8793,12 @@ static Field *create_tmp_field_from_item(THD *thd, Item *item, TABLE *table,
   
     enum enum_field_types type;
     /*
-      DATE/TIME fields have STRING_RESULT result type. To preserve
-      type they needed to be handled separately.
+      DATE/TIME and GEOMETRY fields have STRING_RESULT result type. 
+      To preserve type they needed to be handled separately.
     */
     if ((type= item->field_type()) == MYSQL_TYPE_DATETIME ||
         type == MYSQL_TYPE_TIME || type == MYSQL_TYPE_DATE ||
-        type == MYSQL_TYPE_TIMESTAMP)
+        type == MYSQL_TYPE_TIMESTAMP || type == MYSQL_TYPE_GEOMETRY)
       new_field= item->tmp_table_field_from_field_type(table);
     /* 
       Make sure that the blob fits into a Field_varstring which has