当数据插入到同一表中具有相同值的另一个cloum时，如何在postgres中编写触发器以更新另一列？

Question

Please Find below Table structure:-

CREATE TABLE emp (
    empname  text NOT NULL,
    salary  integer,
    salary1 integer
);

Whenever i will insert data into emp table using below query salary1 column should be filled automatically using trigger in postgres ?

insert into emp(empname,salary) values('Tarik','1200');

I have tried below code,But it is not working for me.

CREATE OR REPLACE FUNCTION employee_insert_trigger_fnc()
  RETURNS trigger AS
$$
BEGIN
    update emp set salary1=NEW.salary where NEW.salary=NEW.salary;
RETURN NEW;
END;
$$
LANGUAGE 'plpgsql';

create TRIGGER employee_insert_trigger
AFTER Insert
 ON emp
FOR EACH ROW
EXECUTE PROCEDURE employee_insert_trigger_fnc();

Please help.. Thanks in advance.

Answer 1

Issue resolved after my R&D:-

CREATE OR REPLACE FUNCTION employee_insert_trigger_fnc()
  RETURNS trigger AS
$$
BEGIN
        NEW.salary1 := NEW.salary;
RETURN NEW;
END;
$$
LANGUAGE 'plpgsql';

create TRIGGER employee_insert_trigger
BEFORE INSERT OR UPDATE
 ON ami_master.emp
FOR EACH ROW
EXECUTE PROCEDURE employee_insert_trigger_fnc();