ulternative bugfix for BUG#2508 and fix for BUG#2809 - every table has its own TABLE structure

mysql-test/r/union.result:
  fix for union test becuase now not all fields in UNION allow NULLS
  fix of test
  test suite for BUG#2809
mysql-test/t/union.test:
  test suite for BUG#2809
sql/mysql_priv.h:
  removed unused parameter of setup_tables()
sql/sql_base.cc:
  removed unused parameter of setup_tables()
  cleanup of unused code
sql/sql_class.h:
  removed unused field
sql/sql_help.cc:
  removed unused parameter of setup_tables()
sql/sql_insert.cc:
  removed unused parameter of setup_tables()
sql/sql_lex.cc:
  excluded duplicate tables finding for UNION
sql/sql_load.cc:
  removed unused parameter of setup_tables()
sql/sql_olap.cc:
  removed unused parameter of setup_tables()
sql/sql_prepare.cc:
  removed unused parameter of setup_tables()
sql/sql_select.cc:
  removed unused parameter of setup_tables()
  revert old BUG#2508 patch
sql/sql_union.cc:
  revert old BUG#2508 patch
  removed unused code
sql/sql_update.cc:
  removed unused parameter of setup_tables()
sql/table.h:
  shared used only for multi-update for now

1 files changed, 9 insertions, 20 deletions

diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc
index 5ffe8c1c365..96a0a86c43d 100644
--- a/sql/sql_lex.cc
+++ b/sql/sql_lex.cc
@@ -1376,28 +1376,17 @@ create_total_list_n_last_return(THD *thd_arg,
       {
 	TABLE_LIST *cursor;
 	next_table= aux->next;
-	for (cursor= **result_arg; cursor; cursor= cursor->next)
-	  if (!strcmp(cursor->db, aux->db) &&
-	      !strcmp(cursor->real_name, aux->real_name) &&
-	      !strcmp(cursor->alias, aux->alias))
-	    break;
-	if (!cursor)
+	/* Add not used table to the total table list */
+	if (!(cursor= (TABLE_LIST *) thd->memdup((char*) aux,
+						 sizeof(*aux))))
 	{
-	  /* Add not used table to the total table list */
-	  if (!(cursor= (TABLE_LIST *) thd->memdup((char*) aux,
-						   sizeof(*aux))))
-	  {
-	    send_error(thd,0);
-	    return 1;
-	  }
-	  *new_table_list= cursor;
-	  cursor->table_list= aux; //to be able mark this table as shared
-	  new_table_list= &cursor->next;
-	  *new_table_list= 0;			// end result list
+	  send_error(thd,0);
+	  return 1;
 	}
-	else
-	  // Mark that it's used twice
-	  cursor->table_list->shared= aux->shared= 1;
+	*new_table_list= cursor;
+	cursor->table_list= aux;
+	new_table_list= &cursor->next;
+	*new_table_list= 0;			// end result list
 	aux->table_list= cursor;
       }
     }