如何在MySQL中实现这一点:

CREATE TABLE employee (
  employeemonthly DECIMAL(10,2),
  employeeyearly DECIMAL(10,2) DEFAULT employeemonthly*12
);

最佳答案

使用插入触发器。像这样的东西

DELIMITER |

CREATE TRIGGER default_yearly BEFORE INSERT ON employee
  FOR EACH ROW BEGIN
    SET NEW.employeeyearly = NEW.employeemonthly * 12;
  END;
|

DELIMITER ;

10-07 18:26