其他分享
首页 > 其他分享> > 查询出最大年段的客户信息(not exists)

查询出最大年段的客户信息(not exists)

作者:互联网

所用数据库mysql5.7

1、创建表:create table query1(id int not null auto_increment,custId varchar(6),startYear varchar(6),primary key(id))

 

 

 2、插入数据:

INSERT into query1 (custId,startYear) VALUES 
('1','1990'),
('1','1991'),
('1','1992'),
('1','2000'),
('1','2002'),
('1','2002'),
('2','1990'),
('3','1990'),
('3','1990'),
('4','1990'),
('4','1991'),
('4','1992'),
('4','2000'),
('4','2008'),
('4','2008'),
('5','1990'),
('5','1991'),
('5','2000'),
('5','2000'),
('5','2008'),
('5','2008')

3、sql:

select distinct q1.custId,q1.startYear from query1 q1 WHERE
not exists (select '1' from query1 q2 WHERE q1.custId=q2.custId and q1.startYear<q2.startYear)

查看结果:

 

 由于同一个custId可以存着重复的年段,所以用distinct去重

标签:q1,1990,query1,startYear,exists,查询,2000,客户,custId
来源: https://www.cnblogs.com/javasl/p/11519551.html