mysql> SELECT p.type_id,p.type_name,count(s.type_name) AS  FROM tdb_goods_types AS p LEFT JOIN tdb_goods_types AS s ON s.parent_id = p.type_id GROUP BY p.type_name ORDER BY p.type_id;

ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'FROM tdb_goods_types AS p LEFT JOIN tdb_goods_types AS s ON s.parent_id = p.type' at line 1

直接从老师那复制的代码，怎么也运行不对，请教什么原因啊