mysql - Access SQL 查询中的计数函数

Question

按姓名和每位客人在我们酒店预订房间的次数列出客人。按照从最常来的客人到最不常来的客人的顺序排列列表。

我一直在获取 Firstname 和 LastName 的聚合函数

到目前为止我有这段代码

SELECT FirstName, LastName, Count(ResNum) AS TotalReservations
FROM RESERVATION, GUEST
Where GUEST.GuestNo = RESERVATION.GuestNo
ORDER BY RESERVATION.GuestNo

这里是 RelationShip 表的链接

View Relationship Table <--- 链接

Answer 1

试试这个:

SELECT FirstName, LastName, Count(ResNum) AS TotalReservations
FROM RESERVATION
INNER JOIN GUEST ON GUEST.GuestNo = RESERVATION.GuestNo
GROUP BY FirstName, LastName
ORDER BY COUNT(ResNum) DESC