SQLPlus - 跨幾個表的計數功能

Question

我想要統計我的數據中的乘客人數。我無法弄清楚這一點。我的輸出樣本如下所示。數據來自許多不同的表格，我必須加入表格，這不是我遇到的問題。我正在試圖通過描述獲得由EVENT計算的車手數。並仍然顯示如下所述的列。

SQL> SELECT EVENTNAME, DESCRIPTION, RIDERS2 FROM ERP_REPORT; 

EVENTNAME    DESCRIPTION        RIDERS 
------------------------------ ------------------------------ 
Ace Rental Car - Fair Hill Inv Day 1 Race on Fair Hill's Easy Aaron Adams 
itational      level Course 

Ace Rental Car - Fair Hill Inv Day 1 Race on Fair Hill's Easy Aaron Adams 
itational      level Course 

Ace Rental Car - Fair Hill Inv Day 2 Race on Fair Hill's Inte Aaron Adams 
itational      rmediate level Course 

Huffy's Mountain Trip   Weekend 1 Race 1 on Huffy Moun Sam Adams 
          tain's Easy level Course 

Valley Spring Water Mountain B Day 3 Race on Hoola Hut Gorge' Jay Gillgan 
ike Extravaganza    s Intermediate level Course 

我已經嘗試了一堆不同的代碼，但這是一個樣本我試過了。我迷失在此，所以任何幫助都會很大！

SELECT COUNT(DISTINCT RIDERS) as "RIDERS" 
2 FROM ERP_REPORT; 

Answer 1

你是否在尋找類似：

SELECT COUNT(riders) AS rider_count, eventname, description 
    FROM erp_report 
    GROUP BY eventname, description;