摘要: 1、主键自增,姓名字段重复。删除重复的姓名数据,只留一条 -- Every derived table must have its own alias 子查询要起别名-- 思路:分组后只会显示一条,然后根据这一条的id 去not in 删除 DELETE FROM test WHERE id NOT 阅读全文
posted @ 2020-04-22 21:16 詹庆豪 阅读(289) 评论(2) 推荐(0) 编辑