SQL> desc dept
 Name                                                  Null?    Type
 ----------------------------------------------------- -------- ------------------------------------
 DEPTNO                                                         NUMBER(2)
 DNAME                                                          VARCHAR2(14)
 LOC                                                            VARCHAR2(13)

SQL> alter table dept add(new_Col number);

Table altered.

SQL> desc dept
 Name                                                  Null?    Type
 ----------------------------------------------------- -------- ------------------------------------
 DEPTNO                                                         NUMBER(2)
 DNAME                                                          VARCHAR2(14)
 LOC                                                            VARCHAR2(13)
 NEW_COL                                                        NUMBER

SQL> ed
Wrote file afiedt.buf

  1  create table new_dept
  2  as
  3* (select deptno,dname,new_Col,loc from dept)
SQL> /

Table created.

SQL> select * from new_dept;

    DEPTNO DNAME             NEW_COL LOC
---------- -------------- ---------- -------------
        10 ACCOUNTING                NEW YORK
        20 RESEARCH                  DALLAS
        30 SALES                     CHICAGO
        40 OPERATIONS                BOSTON