2017-03-01 36 views
0

我有兩個表,訂單和客戶,我試圖返回沒有訂單的客戶的客戶ID和名稱。在其他表中沒有發生SQL查詢返回條目

customers 
customerID: integer 
name: string 

orders 
orderID: integer 
itemID: integer 
customerID: integer 
date: date 

我目前還沒有返回任何結果:

SELECT customers.customerID, customers.fName, orders.date 
FROM orders INNER JOIN customers 
ON orders.customerID = customers.customerID 
GROUP BY orders.customerID 
HAVING COUNT(*) = 0 
+0

如果你是客戶ID試圖組,並試圖打印3列,查詢將不會工作在第一位。通過http://www.informit.com/articles/article.aspx?p=664143&seqNum=6閱讀寫作小組的基本邏輯 – user1658435

回答

1

你需要一個LEFT OUTER JOIN做到這一點:

SELECT customers.customerID, customers.fName 
FROM customers LEFT OUTER JOIN orders on customers.customerID = orders.customerID 
WHERE orders.customerID IS NULL