Oracle Database Discussions

DB version:10gR2

I know that there is an ALTER TABLE tablename MODIFY command to change the NLS_LENGTH_SEMANTICS for a table column.

I need to change EMP table's Ename and Job column to CHAR. How can i do this with an ALTER command?

SQL>col data_Type format a12
SQL>col column_name format a10
SQL>
SQL>select COLUMN_NAME, DATA_TYPE,DATA_LENGTH, CHAR_LENGTH,CHAR_USED
  2  from dba_tab_columns
  3  where table_name='EMP' and owner = 'SCOTT';

COLUMN_NAM DATA_TYPE    DATA_LENGTH CHAR_LENGTH C
---------- ------------ ----------- ----------- -
EMPNO      NUMBER                22           0
ENAME      VARCHAR2              10          10 B
JOB        VARCHAR2               9           9 B
MGR        NUMBER                22           0
HIREDATE   DATE                   7           0
SAL        NUMBER                22           0
COMM       NUMBER                22           0
DEPTNO     NUMBER                22           0

8 rows selected.