是否可以在Oracle 12c中的另一个表上使用触发器来填充表

Question

Using oracle 12c, I have a table for employee and a table for managers, if the newly inserted employee salary >=5000 then he/she is considered manager. So I'd like to create trigger on table employee that checks if the salary of the newly inserted employee >=5000 this row should be duplicated in the manager table. IS this possible? If yes, could you simply give me the right syntax.

Answer 1

Some general words first: This could be considered bad database design. If you consider an employee beyond a certain salary a manager, this almost screams for a column in the same table, either physical or virtual. For example, it could look like this:

CREATE TABLE employees (
  id          NUMBER,
  first_name  VARCHAR2(10),
  last_name   VARCHAR2(10),
  salary      NUMBER(9,2),
  is_manager  as (case when salary >= 5000 then 1 else 0 end)
  CONSTRAINT employees_pk PRIMARY KEY (id)
);

If you still want to use a trigger and a second managers table, it could work like this:

CREATE OR REPLACE TRIGGER trig_emp_insert
AFTER INSERT
   ON employees
FOR EACH ROW

BEGIN

    if (:new.salary >= 5000) then
        insert into managers (...) values (...)
    end if;

END;