mysql - Access SQL 查询中的计数函数

Question

列出客人的姓名以及每位客人在我们其中一家酒店预订房间的次数。按从最常来客到最不常来客的顺序排列列表。

我不断获得 Firstname 和 LastName 的聚合函数

到目前为止我有这个代码

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

这是关系表的链接

查看关系表 <--- LINK

Answer 1

尝试这个：

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

Answer 2

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