Merge bk@192.168.21.1:mysql-5.0-opt

into  mysql.com:/home/hf/work/8663/my50-8663

5 files changed, 65 insertions, 15 deletions

diff --git a/sql/field.cc b/sql/field.cc
index a09c97fb356..61bbea5e615 100644
--- a/sql/field.cc
+++ b/sql/field.cc
@@ -5639,7 +5639,7 @@ int Field_datetime::store_time(TIME *ltime,timestamp_type type)
                               (MODE_NO_ZERO_IN_DATE | MODE_NO_ZERO_DATE |
                                MODE_INVALID_DATES))), &error))
     {
-      char buff[12];
+      char buff[19];
       String str(buff, sizeof(buff), &my_charset_latin1);
       make_datetime((DATE_TIME_FORMAT *) 0, ltime, &str);
       set_datetime_warning(MYSQL_ERROR::WARN_LEVEL_WARN, WARN_DATA_TRUNCATED,
diff --git a/sql/item.cc b/sql/item.cc
index b26f65ead69..dc92edd651d 100644
--- a/sql/item.cc
+++ b/sql/item.cc
@@ -3707,10 +3707,37 @@ bool Item_field::fix_fields(THD *thd, Item **reference)
         Item** res= find_item_in_list(this, thd->lex->current_select->item_list,
                                       &counter, REPORT_EXCEPT_NOT_FOUND,
                                       &not_used);
-        if (res != (Item **)not_found_item && (*res)->type() == Item::FIELD_ITEM)
+        if (res != (Item **)not_found_item)
         {
-          set_field((*((Item_field**)res))->field);
-          return 0;
+          if ((*res)->type() == Item::FIELD_ITEM)
+          {
+            /*
+             It's an Item_field referencing another Item_field in the select
+             list.
+             use the field from the Item_field in the select list and leave
+             the Item_field instance in place.
+            */
+            set_field((*((Item_field**)res))->field);
+            return 0;
+          }
+          else
+          {
+            /*
+              It's not an Item_field in the select list so we must make a new
+              Item_ref to point to the Item in the select list and replace the
+              Item_field created by the parser with the new Item_ref.
+            */
+            Item_ref *rf= new Item_ref(context, db_name,table_name,field_name);
+            if (!rf)
+              return 1;
+            thd->change_item_tree(reference, rf);
+            /*
+              Because Item_ref never substitutes itself with other items 
+              in Item_ref::fix_fields(), we can safely use the original 
+              pointer to it even after fix_fields()
+             */
+            return rf->fix_fields(thd, reference) ||  rf->check_cols(1);
+          }
         }
       }
       if ((ret= fix_outer_field(thd, &from_field, reference)) < 0)
diff --git a/sql/item_subselect.cc b/sql/item_subselect.cc
index 432a8882f5f..551795acd53 100644
--- a/sql/item_subselect.cc
+++ b/sql/item_subselect.cc
@@ -391,6 +391,15 @@ enum Item_result Item_singlerow_subselect::result_type() const
   return engine->type();
 }
 
+/* 
+ Don't rely on the result type to calculate field type. 
+ Ask the engine instead.
+*/
+enum_field_types Item_singlerow_subselect::field_type() const
+{
+  return engine->field_type();
+}
+
 void Item_singlerow_subselect::fix_length_and_dec()
 {
   if ((max_columns= engine->cols()) == 1)
@@ -1613,32 +1622,36 @@ bool subselect_single_select_engine::no_rows()
 }
 
 
-static Item_result set_row(List<Item> &item_list, Item *item,
-			   Item_cache **row, bool *maybe_null)
+/* 
+ makes storage for the output values for the subquery and calcuates 
+ their data and column types and their nullability.
+*/ 
+void subselect_engine::set_row(List<Item> &item_list, Item_cache **row)
 {
-  Item_result res_type= STRING_RESULT;
   Item *sel_item;
   List_iterator_fast<Item> li(item_list);
+  res_type= STRING_RESULT;
+  res_field_type= FIELD_TYPE_VAR_STRING;
   for (uint i= 0; (sel_item= li++); i++)
   {
     item->max_length= sel_item->max_length;
     res_type= sel_item->result_type();
+    res_field_type= sel_item->field_type();
     item->decimals= sel_item->decimals;
     item->unsigned_flag= sel_item->unsigned_flag;
-    *maybe_null= sel_item->maybe_null;
+    maybe_null= sel_item->maybe_null;
     if (!(row[i]= Item_cache::get_cache(res_type)))
-      return STRING_RESULT; // we should return something
+      return;
     row[i]->setup(sel_item);
   }
   if (item_list.elements > 1)
     res_type= ROW_RESULT;
-  return res_type;
 }
 
 void subselect_single_select_engine::fix_length_and_dec(Item_cache **row)
 {
   DBUG_ASSERT(row || select_lex->item_list.elements==1);
-  res_type= set_row(select_lex->item_list, item, row, &maybe_null);
+  set_row(select_lex->item_list, row);
   item->collation.set(row[0]->collation);
   if (cols() != 1)
     maybe_null= 0;
@@ -1650,13 +1663,14 @@ void subselect_union_engine::fix_length_and_dec(Item_cache **row)
 
   if (unit->first_select()->item_list.elements == 1)
   {
-    res_type= set_row(unit->types, item, row, &maybe_null);
+    set_row(unit->types, row);
     item->collation.set(row[0]->collation);
   }
   else
   {
-    bool fake= 0;
-    res_type= set_row(unit->types, item, row, &fake);
+    bool maybe_null_saved= maybe_null;
+    set_row(unit->types, row);
+    maybe_null= maybe_null_saved;
   }
 }
 
diff --git a/sql/item_subselect.h b/sql/item_subselect.h
index 0c6ba055096..f1be99353cc 100644
--- a/sql/item_subselect.h
+++ b/sql/item_subselect.h
@@ -159,6 +159,7 @@ public:
   my_decimal *val_decimal(my_decimal *);
   bool val_bool();
   enum Item_result result_type() const;
+  enum_field_types field_type() const;
   void fix_length_and_dec();
 
   uint cols();
@@ -311,6 +312,7 @@ protected:
   THD *thd; /* pointer to current THD */
   Item_subselect *item; /* item, that use this engine */
   enum Item_result res_type; /* type of results */
+  enum_field_types res_field_type; /* column type of the results */
   bool maybe_null; /* may be null (first item in select) */
 public:
 
@@ -320,6 +322,7 @@ public:
     result= res;
     item= si;
     res_type= STRING_RESULT;
+    res_field_type= FIELD_TYPE_VAR_STRING;
     maybe_null= 0;
   }
   virtual ~subselect_engine() {}; // to satisfy compiler
@@ -358,6 +361,7 @@ public:
   virtual uint cols()= 0; /* return number of columns in select */
   virtual uint8 uncacheable()= 0; /* query is uncacheable */
   enum Item_result type() { return res_type; }
+  enum_field_types field_type() { return res_field_type; }
   virtual void exclude()= 0;
   bool may_be_null() { return maybe_null; };
   virtual table_map upper_select_const_tables()= 0;
@@ -368,6 +372,9 @@ public:
   virtual bool is_executed() const { return FALSE; }
   /* Check if subquery produced any rows during last query execution */
   virtual bool no_rows() = 0;
+
+protected:
+  void set_row(List<Item> &item_list, Item_cache **row);
 };
 
 
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index f92217302f8..cfc068cec86 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -2951,10 +2951,12 @@ add_key_fields(JOIN *join, KEY_FIELD **key_fields, uint *and_level,
           join->unit->item->substype() == Item_subselect::IN_SUBS &&
           !join->unit->first_select()->next_select())
       {
+        KEY_FIELD *save= *key_fields;
         add_key_fields(join, key_fields, and_level, cond, usable_tables,
                        sargables);
         // Indicate that this ref access candidate is for subquery lookup:
-        (*key_fields)[-1].outer_ref= TRUE;
+        for (; save != *key_fields; save++)
+          save->outer_ref= TRUE;
       }
       return;
     }