sql easy
思路一
select Name as Customersfrom Customers c where Id not in (select CustomerId from Orders);
思路二
select c.Name as Customers
from Customers c left join Orders o
on c.Id = o.CustomerId where o.CustomerId is null;
sql easy
思路一
select Name as Customersfrom Customers c where Id not in (select CustomerId from Orders);
思路二
select c.Name as Customers
from Customers c left join Orders o
on c.Id = o.CustomerId where o.CustomerId is null;
让时间为你证明