一个SQL语句，求助[初学者] - 编程论坛

#2

hu9jj2015-07-31 05:52

没有推荐任何人的特征是什么呢？你凭什么认定vip4和vip8就没有推荐任何人？

#3

kinvanhon2015-07-31 08:30

select ID from member where ID not exists (select distinct tuijianid from member)

#4

mywisdom882015-07-31 16:53

3楼的是SQL语法，
在VFP9中，改为
select ID from member where ID not in (select distinct tuijianid from member)
**
CREATE CURSOR member(id c(12),tuijianid c(12))
**ID tuijianid
INSERT INTO member(id,tuijianid) values('vip1','vip0')
INSERT INTO member(id,tuijianid) values('vip2','vip1')
INSERT INTO member(id,tuijianid) values('vip3','vip2')
INSERT INTO member(id,tuijianid) values('vip4','vip0')
INSERT INTO member(id,tuijianid) values('vip5','vip3')
INSERT INTO member(id,tuijianid) values('vip6','vip5')
INSERT INTO member(id,tuijianid) values('vip7','vip6')
INSERT INTO member(id,tuijianid) values('vip8','vip7')
INSERT INTO member(id,tuijianid) values('vip9','vip2')
INSERT INTO member(id,tuijianid) values('vip10','vip9')
select ID from member where ID not in (select distinct tuijianid from member)

#5

mywisdom882015-07-31 17:08

CREATE CURSOR member(id c(12),tuijianid c(12))
INSERT INTO member(id,tuijianid) values('vip1','vip0')
INSERT INTO member(id,tuijianid) values('vip2','vip1')
INSERT INTO member(id,tuijianid) values('vip3','vip2')
INSERT INTO member(id,tuijianid) values('vip4','vip0')
INSERT INTO member(id,tuijianid) values('vip5','vip3')
INSERT INTO member(id,tuijianid) values('vip6','vip5')
INSERT INTO member(id,tuijianid) values('vip7','vip6')
INSERT INTO member(id,tuijianid) values('vip8','vip7')
INSERT INTO member(id,tuijianid) values('vip9','vip2')
INSERT INTO member(id,tuijianid) values('vip10','vip9')
**大家注意了，问题来了。
**方法1：
select distinct RTRIM(tuijianid) as tjid from member INTO CURSOR aa
select ID from member where rtrim(ID) NOT in (SELECT tjid FROM aa)
**结果是：vip4,vip8,vip10
select ID from member where RTRIM(ID) not in (select distinct RTRIM(tuijianid) as tjid from member)
**方法2：
**结果是：vip4,vip8,,,,为什么vip10不出现在这？VPF9

#6

tlliqi2015-08-01 06:42

没看明白呢

#7

hu9jj2015-08-02 10:59

以下是引用tlliqi在2015-8-1 06:42:35的发言：

没看明白呢

我也是许多才明白的，实际上是筛选在推荐者人字段中不存在的ID号，即没有推荐过任何人的ID。

#8

liwt0072015-08-02 13:59

select t.ID from member m,member t where m.tuijianid != t.ID;

[ 本帖最后由 liwt007 于 2015-8-2 14:02 编辑 ]