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Mysql 然后按组点菜?_Mysql_Join - Fatal编程技术网

Mysql 然后按组点菜?

Mysql 然后按组点菜?,mysql,join,Mysql,Join,我有两个表,第一个是hotel\u info,其中包含的字段有(hotel\u id,hotel\u name,location)和第二个表rooms,其中包含房间信息,如(room\u id,hotel\u id,rate,description)。我需要一个查询,返回酒店的最低房价以及hotel\u info表中关于酒店的所有信息。到目前为止,我的查询工作正常,但没有返回最低房价 SELECT a.hotel_id,a.hotel_name ,a.location, b.rate FROM

我有两个表,第一个是
hotel\u info
,其中包含的字段有(
hotel\u id
hotel\u name
location
)和第二个表
rooms
,其中包含房间信息,如(
room\u id
hotel\u id
rate
description
)。我需要一个查询,返回酒店的最低房价以及
hotel\u info
表中关于酒店的所有信息。到目前为止,我的查询工作正常,但没有返回最低房价

SELECT a.hotel_id,a.hotel_name ,a.location, b.rate FROM hotel_info a 
LEFT JOIN rooms b ON b.hotel_id=a.hotel_id 
GROUP BY hotel_id

如何获得每家酒店的最低房价?

您可以使用mysql函数min()

select a.hotel_id, min(b.rate) 
from hotel_info a 
left join rooms b on b.hotel_id = a.hotel_id 
group by a.hotel_id;
SELECT a.hotel_id, a.hotel_name, a.location, min(b.rate) as min_rate 
FROM hotel_info a 
LEFT JOIN rooms b ON b.hotel_id = a.hotel_id 
GROUP BY a.hotel_id, a.hotel_name, a.location