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PHP mysql如何查询某个字段有多少个不同的值

WBOY
Release: 2016-06-23 13:01:57
Original
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举个例子,
在car表有个pinpai字段,
有Lambo,Audi,BMW,Audi,Toyota,Lambo 6个值,
那么这个字段有4个不同的品牌,6辆车
求解如何得出4这个值和6这个值
前台显示的是:"现共有4种品牌车辆,共计6辆。"
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求大神给个完整的sql select语句 本人新手求实力老司机指点
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不要复制粘贴 
select pinpai from car group by pinpai 和 select distinct pinpai from car
不是我要的答 因为他们之中缺少数量


回复讨论(解决方案)

create temporary table car (pinpai varchar(10));insert into car values ('Lambo'),('Audi'),('BMW'),('Audi'),('Toyota'),('Lambo');select pinpai, count(*) as cnt from car group by 1
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Copy after login
pinpai cnt Audi   2 BMW    1 Lambo  2 Toyota 1 
Copy after login
Copy after login

你没有理解我的意思,你这不是我要的结果,我是要显示 前台显示的是:"现共有4种品牌车辆,共计6辆。" 而不是 把它们每个品牌有多少个显示出来

create temporary table car (pinpai varchar(10));insert into car values ('Lambo'),('Audi'),('BMW'),('Audi'),('Toyota'),('Lambo');select pinpai, count(*) as cnt from car group by 1
Copy after login
Copy after login
pinpai cnt Audi   2 BMW    1 Lambo  2 Toyota 1 
Copy after login
Copy after login

你没有理解我的意思,你这不是我要的结果,我是要显示 前台显示的是:"现共有4种品牌车辆,共计6辆。" 而不是 把它们每个品牌有多少个显示出来

使用group by + count(*)就可以了.

select pinpai, count(*) as num from car group by pinpai;

select count(*) pinpai, sum(cnt) as cnt  from (select pinpai, count(*) as cnt from car group by 1) T
Copy after login
Copy after login
pinpai cnt 4      6 
Copy after login
Copy after login

你是一点数据库知识都不学?

select count(*) pinpai, sum(cnt) as cnt  from (select pinpai, count(*) as cnt from car group by 1) T
Copy after login
Copy after login
pinpai cnt 4      6 
Copy after login
Copy after login

你是一点数据库知识都不学?

 
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