Fix for Bug#5615 and merge from 4.1

mysql-test/r/func_group.result:
  Added some tests and fix for Bug#5615.
mysql-test/r/show_check.result:
  Fix for Bug#5615.
mysql-test/t/func_group.test:
  Added some tests.
sql/item_sum.cc:
  Fix for Bug#5615.
sql/item_sum.h:
  Fix for Bug#5615.
sql/sql_select.cc:
  Fix for Bug#5615.
sql/sql_select.h:
  Fix for Bug#5615.

4 files changed, 26 insertions, 7 deletions

diff --git a/sql/item_sum.cc b/sql/item_sum.cc
index b4a53ba0f80..dbba02c3cf7 100644
--- a/sql/item_sum.cc
+++ b/sql/item_sum.cc
@@ -22,6 +22,7 @@
 #endif
 
 #include "mysql_priv.h"
+#include "sql_select.h"
 
 Item_sum::Item_sum(List<Item> &list)
   :arg_count(list.elements)
@@ -303,6 +304,21 @@ Item_sum_hybrid::fix_fields(THD *thd, TABLE_LIST *tables, Item **ref)
   return FALSE;
 }
 
+Field *Item_sum_hybrid::create_tmp_field(bool group, TABLE *table,
+					 uint convert_blob_length)
+{
+  if (args[0]->type() == Item::FIELD_ITEM)
+  {
+    Field *field= ((Item_field*) args[0])->field;
+    
+    if ((field= create_tmp_field_from_field(current_thd, field, this, table,
+					    0, convert_blob_length)))
+      field->flags&= ~NOT_NULL_FLAG;
+    return field;
+  }
+  return Item_sum::create_tmp_field(group, table, convert_blob_length);
+}
+
 
 /***********************************************************************
 ** reset and add of sum_func
@@ -2075,8 +2091,6 @@ my_decimal *Item_variance_field::val_decimal(my_decimal *dec_buf)
 ** COUNT(DISTINCT ...)
 ****************************************************************************/
 
-#include "sql_select.h"
-
 int simple_str_key_cmp(void* arg, byte* key1, byte* key2)
 {
   Item_sum_count_distinct* item = (Item_sum_count_distinct*)arg;
diff --git a/sql/item_sum.h b/sql/item_sum.h
index 81f5d45e42e..fead45f1881 100644
--- a/sql/item_sum.h
+++ b/sql/item_sum.h
@@ -94,7 +94,6 @@ public:
   Item *get_tmp_table_item(THD *thd);
   virtual Field *create_tmp_field(bool group, TABLE *table,
                                   uint convert_blob_length);
-
   bool walk (Item_processor processor, byte *argument);
 };
 
@@ -525,6 +524,8 @@ protected:
   void cleanup();
   bool any_value() { return was_values; }
   void no_rows_in_result();
+  Field *create_tmp_field(bool group, TABLE *table,
+			  uint convert_blob_length);
 };
 
 
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index cbe7937355c..e886c658444 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -7593,10 +7593,10 @@ const_expression_in_where(COND *cond, Item *comp_item, Item **const_item)
     new_created field
 */
 
-static Field* create_tmp_field_from_field(THD *thd, Field* org_field,
-                                          Item *item, TABLE *table,
-                                          bool modify_item,
-                                          uint convert_blob_length)
+Field* create_tmp_field_from_field(THD *thd, Field* org_field,
+				   Item *item, TABLE *table,
+				   bool modify_item,
+				   uint convert_blob_length)
 {
   Field *new_field;
 
diff --git a/sql/sql_select.h b/sql/sql_select.h
index 0f26207b391..1b7893dbc7c 100644
--- a/sql/sql_select.h
+++ b/sql/sql_select.h
@@ -399,6 +399,10 @@ void copy_funcs(Item **func_ptr);
 bool create_myisam_from_heap(THD *thd, TABLE *table, TMP_TABLE_PARAM *param,
 			     int error, bool ignore_last_dupp_error);
 uint find_shortest_key(TABLE *table, const key_map *usable_keys);
+Field* create_tmp_field_from_field(THD *thd, Field* org_field,
+				   Item *item, TABLE *table,
+				   bool modify_item,
+				   uint convert_blob_length);
 
 /* functions from opt_sum.cc */
 bool simple_pred(Item_func *func_item, Item **args, bool *inv_order);