Fix for BUG#13410 - qualified reference to a view column in the HAVING clause cannot be resolved.

The problem was then when a column reference was resolved to a view column, the new Item
created for this column contained the name of the view, and not the view alias.


mysql-test/r/view.result:
  Additional test for BUG#13410.
mysql-test/t/view.test:
  Additional test for BUG#13410.
sql/item.cc:
  Correctly cast 'cur_field' to Item_ident because if the original item is
  an Item_field, the cur_field is either an Item_field or an Item_ref.
  Thus we have to cast cur_field to a common super-class of both.
sql/item.h:
  - real_item() may be called before Item_ref::ref is set
    (i.e. the Item_ref object was resolved).
  - To avoid a crash and to return some meaningful value
    in such cases we return 'this'.
sql/sql_base.cc:
  - 'item' may be an Item_ref, so we test for the type of the actual
    referenced item.
  - Correctly cast 'cur_field' to Item_ident because if the original
    item is an Item_field, the cur_field is either an Item_field or an
    Item_ref. Thus we have to cast cur_field to a common super-class
    of both.
sql/table.cc:
  - When creating a new Item for a reference to a view column, use the view alias,
    and not the real view name.
  - Removed old code

1 files changed, 2 insertions, 2 deletions

diff --git a/sql/item.cc b/sql/item.cc
index f826fc1d874..966dbbaec53 100644
--- a/sql/item.cc
+++ b/sql/item.cc
@@ -2973,7 +2973,7 @@ static Item** find_field_in_group_list(Item *find_item, ORDER *group_list)
   const char *field_name;
   ORDER      *found_group= NULL;
   int         found_match_degree= 0;
-  Item_field *cur_field;
+  Item_ident *cur_field;
   int         cur_match_degree= 0;
 
   if (find_item->type() == Item::FIELD_ITEM ||
@@ -2992,7 +2992,7 @@ static Item** find_field_in_group_list(Item *find_item, ORDER *group_list)
   {
     if ((*(cur_group->item))->real_item()->type() == Item::FIELD_ITEM)
     {
-      cur_field= (Item_field*) *cur_group->item;
+      cur_field= (Item_ident*) *cur_group->item;
       cur_match_degree= 0;
       
       DBUG_ASSERT(cur_field->field_name != 0);