Question

我有两张桌子：客户（id，name，advisorID）和员工（id，name，managerID）

从员工表中删除员工时，如何触发更新客户顾问ID为已删除员工managerID的值？

到目前为止，我有：

CREATE TRIGGER updateAdvisor BEFORE DELETE ON Employee
   BEGIN
      UPDATE Customer set Customer.advisorID = Employee.managerID 
      from Employee
      WHERE Employee.managerID IN(
          SELECT managerID
          FROM Employee)

感谢您的帮助!!

Answer 1

UPDATE语句适用于单个表;你必须用correlated subquery：

查找新值

UPDATE Customer
SET advisorID = (SELECT managerID
                 FROM Employee
                 WHERE Employee = OLD.EmployeeID)
...

此外，您只想更新那些实际拥有待删除员工的客户作为顾问：

...
WHERE advisorID = OLD.EmployeeID;

Answer 2

这很棒！

CREATE TRIGGER updateAdvisor BEFORE DELETE ON employee
BEGIN
UPDATE customer
SET advisorID = (SELECT managerID FROM employee WHERE employeeID = old.employeeID)
WHERE advisorID = old.employeeID;
END;

删除更新元组的sqlite触发器与另一个表的值？

2 个答案: