How to get name of the employee while triggering his salary?

Question

create or replace trigger trg_t3 after  
    insert OR update or delete of salary  on t2 
    for each row  
begin 
   if 
    to_char(systimestamp,'hh24') not between 9 and 17 
   then 
    insert into  t3  values (:new.salary, :old.salary, sysdate);
   else
     DBMS_OUTPUT.put_line ('update is not possible  between 9:00 and 17:00');
   end if;        
end; 
/

this will insert old salary ,new salary and the time on table t3 based on the conditions mentioned in trigger on table t2. But i need the name of the employee whose salary is updated or delete.

if i am updating a salary on t2 i need to insert the name of the specific employee whose salary i have modified into t3. But current method will only insert old salary, new salary and time

here is the code for creating the tables

create table t2 ( name varchar(20), salary varchar2(20));
create table t3 (salary_new   varchar2(50), salary_old  varchar2(20), log_date date);

insert all 
into t2 values('hari',2000) 
into t2 values('sam',40000)
into t2 values('ravi',60000)
into t2 values('manoj',8000)
into t2 values('pratheep',10000)
into t2 values('john',3000)
into t2 values('joe',50000)
into t2 values('scott',70000)
select * from dual;

Answer 1

Your trigger is marked as after insert or update or delete. You have to handle all three situations otherwise it will not work correctly, because when inserting we have no :old values and when deleting there are no :new.

So if you use :new.name then delete will put null value. If you use :old.name then insert will not work correctly. Use variable or do it like here:

create or replace trigger trg_t3 after
  insert or update or delete of salary on t2 for each row
begin
  if to_char(systimestamp,'hh24') between 9 and 17 then
    dbms_output.put_line ('update is not possible between 9:00 and 17:00');
  else
    if deleting then
      insert into t3 (salary_new, salary_old, name, log_date)
        values (null, :old.salary, :old.name, sysdate);
    elsif inserting then
      insert into t3 (salary_new, salary_old, name, log_date)
        values (:new.salary, null, :new.name, sysdate);
    elsif updating then
      insert into t3 (salary_new, salary_old, name, log_date)
        values (:new.salary, :old.salary, :new.name, sysdate);
    end if;
  end if;
end;