Question

我有4张桌子：

客户
帐户
付款
转移

我希望得到转移或付款的客户。付款表链接到客户表，转移表链接到帐户表，帐户表链接到客户表。

如何编写返回付款或转帐客户的查询？

SELECT customer.registration_os, Count(DISTINCT customer.customer_id) AS registrations 
FROM customer
Inner Join account On customer.customer_id = account.customer_id
INNER JOIN payment ON customer.customer_id = payment.customer_id 
LEFT JOIN transfer ON customer.customer_id= transfer.from_account 
WHERE customer.ts_created BETWEEN ? AND ? 
  AND customer.registration_source = ? 
GROUP BY customer.registration_os

谢谢

Answer 1

SELECT * FROM Customers as t1 
LEFT JOIN Accounts as t2 ON t2.customer_id = t1.id // (Account table is linked to Customers)
LEFT JOIN Payments as t3 ON t3.customer_id = t3.id //  (Payments table is linked to Customers)
LEFT JOIN Transfers as t4 ON t4.account_id = t2.id // (Transfers table is linked to Accounts)
WHERE (condition)

对于基于表名的条件使用参数，我已经给出了t1，t2，t3，t4你可以使用条件中的任何表。

Answer 2

我希望得到转帐或付款的客户

在SQL中，UNION类似于逻辑OR：

  SELECT customer_id
    FROM customer NATURAL JOIN account
  UNION
  SELECT customer_id
    FROM customer NATURAL JOIN ( SELECT from_account AS customer_id 
                                    FROM transfer ) t

SQL连接在不同的表之间

2 个答案: