fixed union types merging and table related metadata (BUG#8824)

mysql-test/r/func_group.result:
  new result
mysql-test/r/metadata.result:
  new result
  test of metadata of variables, unions and derived tables
mysql-test/r/union.result:
  new results
  test of union of enum
mysql-test/t/metadata.test:
  test of metadata of variables, unions and derived tables
mysql-test/t/union.test:
  test of union of enum
sql/field.cc:
  Field type merging rules added
  Fixed table name/alias returting for field made from temporary tables
sql/field.h:
  removed unned field type reporting
sql/item.cc:
  fixed bug in NEW_DATE type field creartion
  replaced mechanism of merging types of UNION
sql/item.h:
  replaced mechanism of merging types of UNION
sql/item_func.h:
  new item type to make correct field type detection possible
sql/item_subselect.cc:
  added table name parameter to prepare() to show right table alias for derived tables
sql/sql_derived.cc:
  added table name parameter to prepare() to show right table alias for derived tables
sql/sql_lex.h:
  added table name parameter to prepare() to show right table alias for derived tables
sql/sql_parse.cc:
  made function for enum/set pack length calculation
sql/sql_prepare.cc:
  added table name parameter to prepare() to show right table alias for derived tables
sql/sql_select.cc:
  new temporary table field creation by Item_type_holder
  fixed table alias for temporary table
sql/sql_union.cc:
  added table name parameter to prepare() to show right table alias for derived tables

1 files changed, 2 insertions, 2 deletions

diff --git a/sql/sql_derived.cc b/sql/sql_derived.cc
index 3e627243b9f..e9f9b432c21 100644
--- a/sql/sql_derived.cc
+++ b/sql/sql_derived.cc
@@ -123,7 +123,7 @@ static int mysql_derived(THD *thd, LEX *lex, SELECT_LEX_UNIT *unit,
     DBUG_RETURN(1); // out of memory
 
   // st_select_lex_unit::prepare correctly work for single select
-  if ((res= unit->prepare(thd, derived_result, 0)))
+  if ((res= unit->prepare(thd, derived_result, 0, org_table_list->alias)))
     goto exit;
 
 	
@@ -161,7 +161,7 @@ static int mysql_derived(THD *thd, LEX *lex, SELECT_LEX_UNIT *unit,
     if (is_union)
     {
       // execute union without clean up
-      if (!(res= unit->prepare(thd, derived_result, SELECT_NO_UNLOCK)))
+      if (!(res= unit->prepare(thd, derived_result, SELECT_NO_UNLOCK, "")))
 	res= unit->exec();
     }
     else