Question

我必须在DBMS中更新我的表。无法弄清楚为什么我会收到此错误。

  UPDATE Customers
  SET CreditLimit = CreditLimit * 1.25
      FROM(SELECT *
           FROM Orders
           WHERE Amount > 250
           HAVING COUNT(*) >= 2);

有什么想法吗？

Answer 1

UPDATE Customers
      SET CreditLimit = CreditLimit * 1.25
          FROM Customers
    Where Id in (
     select CustomerId 
     from orders 
     where  Amount > 250
     Group By CustomerId
     HAVING COUNT(*) >= 2);

或

UPDATE Customers
      SET CreditLimit = CreditLimit * 1.25
          FROM Customers c
    Where (select count(*) from orders o where o.CustomerId = c.Id And Amount > 250) > =2

Answer 2

update语句没有像您指定的from子句你想做这样的事情： 对于拥有至少2笔订单超过250美元的客户，将信用额度提高25％。

update Customers
   set CreditLimit = CreditLimit * 1.25
 where (select count(*)
          from Orders
         where Amount > 250
           and orders.customer_id = Customers.customer_id)) >= 2;

修改
我刚刚注意到你正在使用Oracle（ORA消息）。由于您可能会更新所有客户，我认为最高效的方法是使用“可更新连接”或下面的合并语句：

merge into customers using (select customer_id from Orders o where amount > 250 group by customer_id having count(*) >= 2 ) orders on(customers.customer_id = orders.customer_id) when matched then update set customers.creditlimit = customers.creditlimit * 1.25;

初学者sql问题pt.2错误ora-00933 SQL命令没有正确结束

2 个答案: