加入2个不同列的表

Question

银行数据库架构:

account    (account_number, branch_name, balance) 
branch     (branch_name, branch_city, assets) 
customer   (customer_name customer_street, customer_city) 
loan       (loan_number, branch_name, amount) 
deposito   (customer_name, account_number) 
borrower   (customer_name, loan_number) 

我怎么知道借款人的账号？

Answer 1

试试这个..(根据你的评论)

SELECT c.customer_name,
  a.account_number
FROM customer c
  INNER JOIN depositor d
    ON c.customer_name = d.customer_name
  INNER JOIN borrower b
    ON d.customer_name = b.customer_name
  INNER JOIN account a
    ON a.account_number = d.account_number

见DEMO

更新:

SELECT b.customer_name,
  d.account_number
FROM borrower b
  INNER JOIN depositor d
    ON d.customer_name = b.customer_name
  INNER JOIN account a
ON a.account_number = d.account_number

见DEMO