total table list managment is changed

sql/sql_lex.cc

@@ -996,3 +996,79 @@ void st_select_lex_node::exclude()
        master->slave= next;
   */
 }
+
+/*
+  This is used for UNION & subselect to create a new table list of all used 
+  tables.
+  The table_list->table entry in all used tables are set to point
+  to the entries in this list.
+*/
+
+// interface
+bool st_select_lex_unit::create_total_list(THD *thd, st_lex *lex,
+					   TABLE_LIST **result)
+{
+  *result= 0;
+  return create_total_list_n_last_return(thd, lex, &result);
+}
+
+// list creator
+bool st_select_lex_unit::create_total_list_n_last_return(THD *thd, st_lex *lex,
+							 TABLE_LIST ***result)
+{
+  TABLE_LIST *slave_list_first=0, **slave_list_last= &slave_list_first;
+  TABLE_LIST **new_table_list= *result, *aux;
+  SELECT_LEX *sl= (SELECT_LEX*)slave;
+  for (; sl; sl= (SELECT_LEX*)sl->next)
+  {
+    // check usage of ORDER BY in union
+    if (sl->order_list.first && sl->next && !sl->braces)
+    {
+      net_printf(&thd->net,ER_WRONG_USAGE,"UNION","ORDER BY");
+      return 1;
+    }
+    if (sl->slave)
+      if (((SELECT_LEX_UNIT *)
+	   sl->slave)->create_total_list_n_last_return(thd, lex,
+						       &slave_list_last))
+	return 1;
+    if ((aux= (TABLE_LIST*) sl->table_list.first))
+    {
+      TABLE_LIST *next;
+      for (; aux; aux= next)
+      {
+	TABLE_LIST *cursor;
+	next= aux->next;
+	for (cursor= **result; cursor; cursor= cursor->next)
+	  if (!strcmp(cursor->db, aux->db) &&
+	      !strcmp(cursor->real_name, aux->real_name) &&
+	      !strcmp(cursor->name, aux->name))
+	    break;
+	if (!cursor)
+	{
+	  /* Add not used table to the total table list */
+	  aux->lock_type= lex->lock_option;
+	  if (!(cursor= (TABLE_LIST *) thd->memdup((char*) aux,
+						   sizeof(*aux))))
+	  {
+	    send_error(&thd->net,0);
+	    return 1;
+	  }
+	  *new_table_list= cursor;
+	  new_table_list= &cursor->next;
+	  *new_table_list= 0;			// end result list
+	}
+	else
+	  aux->shared= 1;			// Mark that it's used twice
+	aux->table_list= cursor;
+      }
+    }
+  }
+  if (slave_list_first)
+  {
+    *new_table_list= slave_list_first;
+    new_table_list= slave_list_last;
+  }
+  *result= new_table_list;
+  return 0;
+}

sql/sql_lex.h

@@ -207,6 +207,7 @@ struct st_select_lex_node {
    SELECT_LEX_UNIT - unit of selects (UNION, INTERSECT, ...) group 
    SELECT_LEXs
 */
+struct st_lex;
 struct st_select_lex_unit: public st_select_lex_node {
   /*
     Pointer to 'last' select or pointer to unit where stored
@@ -216,6 +217,10 @@ struct st_select_lex_unit: public st_select_lex_node {
   /* LIMIT clause runtime counters */
   ha_rows select_limit_cnt, offset_limit_cnt;
   void init_query();
+  bool create_total_list(THD *thd, st_lex *lex, TABLE_LIST **result);
+private:
+  bool create_total_list_n_last_return(THD *thd, st_lex *lex,
+				       TABLE_LIST ***result);
 };
 typedef struct st_select_lex_unit SELECT_LEX_UNIT;
 

sql/sql_parse.cc

@@ -70,7 +70,6 @@ static void remove_escape(char *name);
 static void refresh_status(void);
 static bool append_file_to_dir(THD *thd, char **filename_ptr,
 			       char *table_name);
-static bool create_total_list(THD *thd, LEX *lex, TABLE_LIST **result);
 
 const char *any_db="*any*";	// Special symbol for check_access
 
@@ -1247,7 +1246,8 @@ mysql_execute_command(void)
 					   cursor))
 	DBUG_VOID_RETURN;
   }
-  if ((lex->select_lex.next && create_total_list(thd,lex,&tables)) ||
+  if ((lex->select_lex.link_next && 
+       lex->unit.create_total_list(thd, lex, &tables)) ||
       (table_rules_on && tables && thd->slave_thread &&
        !tables_ok(thd,tables)))
     DBUG_VOID_RETURN;
@@ -1942,7 +1942,7 @@ mysql_execute_command(void)
 	goto error;
       }
       auxi->lock_type=walk->lock_type=TL_WRITE;
-      auxi->table= (TABLE *) walk;		// Remember corresponding table
+      auxi->table_list=  walk;		// Remember corresponding table
     }
     tables->grant.want_privilege=(SELECT_ACL & ~tables->grant.privilege);
     if (add_item_to_list(new Item_null()))
@@ -1955,7 +1955,7 @@ mysql_execute_command(void)
       break;
     /* Fix tables-to-be-deleted-from list to point at opened tables */
     for (auxi=(TABLE_LIST*) aux_tables ; auxi ; auxi=auxi->next)
-      auxi->table= ((TABLE_LIST*) auxi->table)->table;
+      auxi->table= auxi->table_list->table;
     if (!thd->fatal_error && (result=new multi_delete(thd,aux_tables,
 						      lex->lock_option,table_count)))
     {
@@ -3193,68 +3193,6 @@ TABLE_LIST *add_table_to_list(Table_ident *table, LEX_STRING *alias,
 }
 
 
-/*
-** This is used for UNION to create a new table list of all used tables
-** The table_list->table entry in all used tables are set to point
-** to the entries in this list.
-*/
-
-static bool create_total_list(THD *thd, LEX *lex, TABLE_LIST **result)
-{
-  /* Handle the case when we are not using union */
-  if (!lex->select_lex.next)
-  {
-    *result= (TABLE_LIST*) lex->select_lex.table_list.first;
-    return 0;
-  }
-
-  SELECT_LEX *sl;
-  TABLE_LIST **new_table_list= result, *aux;
-
-  *new_table_list= 0;				// end result list
-  for (sl= &lex->select_lex; sl; sl= (SELECT_LEX *) sl->next)
-  {
-    if (sl->order_list.first && sl->next && !sl->braces)
-    {
-      net_printf(&thd->net,ER_WRONG_USAGE,"UNION","ORDER BY");
-      return 1;
-    }
-    if ((aux= (TABLE_LIST*) sl->table_list.first))
-    {
-      TABLE_LIST *next;
-      for (; aux; aux=next)
-      {
-	TABLE_LIST *cursor;
-	next= aux->next;
-	for (cursor= *result; cursor; cursor=cursor->next)
-	  if (!strcmp(cursor->db,aux->db) &&
-	      !strcmp(cursor->real_name,aux->real_name) &&
-	      !strcmp(cursor->name, aux->name))
-	    break;
-	if (!cursor)
-	{
-	  /* Add not used table to the total table list */
-	  aux->lock_type= lex->lock_option;
-	  if (!(cursor = (TABLE_LIST *) thd->memdup((char*) aux,
-						    sizeof(*aux))))
-	  {
-	    send_error(&thd->net,0);
-	    return 1;
-	  }
-	  *new_table_list= cursor;
-	  new_table_list= &cursor->next;
-	  *new_table_list=0;			// end result list
-	}
-	else
-	  aux->shared=1;			// Mark that it's used twice
-	aux->table=(TABLE *) cursor;
-      }
-    }
-  }
-  return 0;
-}
-
-
 void add_join_on(TABLE_LIST *b,Item *expr)
 {
   if (!b->on_expr)

sql/sql_union.cc

@@ -48,7 +48,7 @@ int mysql_union(THD *thd, LEX *lex,select_result *result)
     for (TABLE_LIST *cursor= (TABLE_LIST *)sl->table_list.first;
 	 cursor;
 	 cursor=cursor->next)
-      cursor->table= ((TABLE_LIST*) cursor->table)->table;
+      cursor->table= cursor->table_list->table;
   }
 
   /* Global option */

sql/table.h

@@ -143,7 +143,15 @@ typedef struct st_table_list {
   struct st_table_list *natural_join;	 /* natural join on this table*/
   /* ... join ... USE INDEX ... IGNORE INDEX */
   List<String>	*use_index, *ignore_index; 
-  TABLE		*table;
+  /*
+    Usually hold reference on opened table, but may hold reference
+    to node of complete list of tables used in UNION & subselect.
+  */
+  union
+  {
+    TABLE          *table;      /* opened table */
+    st_table_list  *table_list; /* pointer to node of list of all tables */
+  };
   GRANT_INFO	grant;
   thr_lock_type lock_type;
   uint		outer_join;		 /* Which join type */