將此語句轉換為sql查詢

Question

顯示包裹號和每個包裹號的顧客數量，僅適用於擁有100個以上顧客的包裹。

SELECT pack_num, COUNT(customer) 
FROM table_name 
GROUP BY pack_num
HAVING COUNT(customer) >100

這個查詢正確嗎？ 如果沒有，請糾正我。

Answer 1

要只計算唯一的客戶，可以在COUNT上添加DISTINCT 。

SELECT pack_num, COUNT(DISTINCT customer) 
FROM table_name 
GROUP BY pack_num
HAVING COUNT(DISTINCT customer) >100