统计查询结果中出现的次数

Question

我在我的 sql server 2012 数据库上运行以下查询。

select Appointment.AppointmentDate, Appointment.AppointmentTime,   Auctioneer.AuctioneerName, Auctioneer.AuctioneerSurname, Buyer.BuyerName,   Buyer.BuyerSurname  
from Appointment  
inner join Auctioneer on Appointment.AuctioneerId=Auctioneer.AuctioneerId  
inner join Buyer on Appointment.BuyerId=Buyer.BuyerId  
where AppointmentDate between '2017-01-01' and '2017-12-31' 

结果如下：

+-----------------+-----------------+----------------+-------------------+-----------+----------------+
| AppointmentDate | AppointmentTime | AuctioneerName | AuctioneerSurname | BuyerName | BuyerSurname   |
+-----------------+-----------------+----------------+-------------------+-----------+----------------+
| 2017-10-23      | 13:00:00        | Mary           | Borg              | David     | Borg           |
| 2017-10-24      | 15:30:00        | Mary           | Borg              | Joseph    | Sammut         |
| 2017-11-03      | 09:30:00        | Joseph         | Smith             | Mark      | Psaila         |
| 2017-11-03      | 10:45:00        | Joseph         | Smith             | David     | Borg           |
| 2017-11-15      | 10:10:00        | Mary           | Borg              | David     | Borg           |
| 2017-08-02      | 08:30:00        | Daisy          | Webb              | Josephine | Grima          |
| 2017-04-15      | 14:00:00        | Sam            | King              | Mary      | Santucci       |
+-----------------+-----------------+----------------+-------------------+-----------+----------------+

我需要添加一个列来计算结果中“AuctioneerName”和“AuctioneeSurname”的出现次数。

示例：玛丽·博格 3 次，约瑟夫·史密斯 2 次等……

Answer 1

我认为你只需要一个窗口count()：

COUNT(*) OVER (PARTITION BY AuctioneerSurname, AuctioneerName)

添加计算的查询 - 并为长表名使用别名：

select 
    app.AppointmentDate,  app.AppointmentTime,
    auc.AuctioneerName,  auc.AuctioneerSurname, 
    buy.BuyerName,  buy.BuyerSurname,
    AuctioneerCount = count(*) over
                         (partition by auc.AuctioneerSurname, auc.AuctioneerName)
from 
    Appointment as app
    inner join Auctioneer as auc 
        on app.AuctioneerId = auc.AuctioneerId  
    inner join Buyer as buy 
        on app.BuyerId = buy.BuyerId  
where
    app.AppointmentDate between '2017-01-01' and '2017-12-31' ;