Help on triggers

Question

FOllowing is the process that I have gone through in creating the tables and trigger.
Now when I try to insert a row into mahesh_emp (while not passing anything for empno), I get an error:
ORA-00947: not enough values
I was asssuming, now that I have a trigger, I will not have to insert anything into that column. But it does not seem like this.
How can I set up mahesh_emp such that I wont have to insert empno and it willl get automatically updated with each inset statement?
CREATE TABLE mahesh_dept (
deptno NUMBER(4) PRIMARY KEY,
dname VARCHAR2(14),
loc VARCHAR2(13));
CREATE TABLE mahesh_emp (
empno NUMBER(4) PRIMARY KEY,
ename VARCHAR2(10),
job VARCHAR2(9),
mgr NUMBER(4),
sal NUMBER(7,2),
comm NUMBER(7,2),
deptno NUMBER(2),
FOREIGN KEY (DEPTNO) REFERENCES DEPT(DEPTNO));
CREATE SEQUENCE mahesh_emp_sequence
INCREMENT BY 1
START WITH 1
NOMAXVALUE
NOCYCLE
CACHE 10;
create or replace trigger mahesh_emp_trigger
before insert on mahesh_emp
for each row
begin
if :new.empno is null then
select mahesh_emp_sequence.nextval
into :new.empno
from dual;
end if;
end;

Answer 1

Much like Todd's explanation the INSERT is the problem. My guess is that the new auto populated column was removed from the VALUES clause, but not from the inserted column list. Unless your coding that bad and not specifying the column names ;).
insert into mahesh_emp
empno (1), (should also be removed)
ename (2),
job (3),
mgr (4),
sal (5),
comm (6),
deptno (7)
values
B (1),
C (2),
D (3),
E (4),
F (5),
G (6)
Or like he said, put a NULL in it's palce in the values list.
Good luck in the future and beyond,
Tyler D.