SQLPlus - 跨几个表的计数功能

Question

我想要统计我的数据中的乘客人数。我无法弄清楚这一点。我的输出样本如下所示。数据来自许多不同的表格，我必须加入表格，这不是我遇到的问题。我正在试图通过描述获得由EVENT计算的车手数。并仍然显示如下所述的列。

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 

我已经尝试了一堆不同的代码，但这是一个样本我试过了。我迷失在此，所以任何帮助都会很大！

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

Answer 1

你是否在寻找类似：

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