How to update a table that has around 1 Million Records

Question

Hi,
Lets take the basic emp table for our Referenece and lets assume that it contains around 60000 Records and all the deptno in that table are Initially 10. Please provide an update statement which would update deptno column of EMP table((based on) order by EMPNO) in for every 120 records incrementing by 1.(DeptNo to be incremented by 1,like 10 ,11 , 12 etc).
First 120 Records deptno should be 10,
Next 120 Records deptno should be 11, and so on.
For Last 120 records deptno should be updated with 500.
Please advise.
Regards,

Answer 1

Ok, I've done it on a smaller set, incrementing every 5 records...
SQL> ed
Wrote file afiedt.buf
  1  update emp2 set deptno = (select newdeptno
  2                            from (select empno, 10+floor((row_number() over (order by empno)-1)/5) as newdeptno
  3                                  from emp2
  4                                 ) e2
  5                            where e2.empno = emp2.empno
  6*                          )
SQL> /
14 rows updated.
SQL> select * from emp2;
     EMPNO ENAME      JOB              MGR HIREDATE                    SAL       COMM     DEPTNO
      7369 SMITH      CLERK           7902 17-DEC-1980 00:00:00        800                    10
      7499 ALLEN      SALESMAN        7698 20-FEB-1981 00:00:00       1600        300         10
      7521 WARD       SALESMAN        7698 22-FEB-1981 00:00:00       1250        500         10
      7566 JONES      MANAGER         7839 02-APR-1981 00:00:00       2975                    10
      7654 MARTIN     SALESMAN        7698 28-SEP-1981 00:00:00       1250       1400         10
      7698 BLAKE      MANAGER         7839 01-MAY-1981 00:00:00       2850                    11
      7782 CLARK      MANAGER         7839 09-JUN-1981 00:00:00       2450                    11
      7788 SCOTT      ANALYST         7566 19-APR-1987 00:00:00       3000                    11
      7839 KING       PRESIDENT            17-NOV-1981 00:00:00       5000                    11
      7844 TURNER     SALESMAN        7698 08-SEP-1981 00:00:00       1500          0         11
      7876 ADAMS      CLERK           7788 23-MAY-1987 00:00:00       1100                    12
      7900 JAMES      CLERK           7698 03-DEC-1981 00:00:00        950                    12
      7902 FORD       ANALYST         7566 03-DEC-1981 00:00:00       3000                    12
      7934 MILLER     CLERK           7782 23-JAN-1982 00:00:00       1300                    12
14 rows selected.but the principle would be the same.