sql 查询不重复记录

来源：百度知道 编辑：UC知道 时间：2024/06/27 15:27:04
SELECT distinct(T_TuPian.PID) as zid,T_TuPian.ClassID, T_TuPian.PanelID, T_TuPian.Title, T_TuPian.UpLoadTime,T_TuPianMingXi.PID as tid, T_TuPianMingXi.Img FROM T_TuPian left JOIN T_TuPianMingXi ON T_TuPian.PID = T_TuPianMingXi.ClassID where T_TuPian.PanelID=1 and T_TuPian.ClassID=1 order by UpLoadTime desc

19 1
18 1
18 1
17 1
16 1
15 1
15 1
15 1
15 1
15 1
15 1
我要查这些字段

可ID 复了

要ID不重复

加了distinct这个也不行

SQL查询不重复记录，操作如下：

1、假如要查询t1表中name字段中所有的姓名，并去除重复。

2、可以使用如下语句：

SELECT DISTINCT name FROM t1;

3、其中DISTINCT是去重功能。

那是因为zid相同,这些字段T_TuPian.PanelID, T_TuPian.Title, T_TuPian.UpLoadTime,T_TuPianMingXi.PID as tid, T_TuPianMingXi.Img 中有不同的,所以不能合并成一行,要么你只查zid和ClassID两个字段,
SELECT distinct(T_TuPian.PID) as zid,T_TuPian.ClassID FROM T_TuPian left JOIN T_TuPianMingXi ON T_TuPian.PID = T_TuPianMingXi.ClassID where T_TuPian.PanelID=1 and T_TuPian.ClassID=1 order by UpLoadTime desc

问题是你用了多表查询，估计你的查询条件不正确，结果返回迪卡尔积了。
两个表的key有没有完全关联呀！