List<Object> list = getList(); return (List<Customer>) list; Compiler says: cannot cast List<Object> to List<Customer> 不能将Object集合强制转换成实体集合! you can always cast any object to any type by up-casting it to Object first. in your cas…
--使用CAST将varchar转换成int类型排序 select distinct(zone_id) from guild_rank_info order by CAST(zone_id as SIGNED); --使用CONVERT将varchar转换成int类型排序 select distinct(zone_id) from guild_rank_info order by convert(zone_id , SIGNED); null…