SQL>
SQL> create table people(
2 employee_id number(9),
3 first_name varchar2(15),
4 last_name varchar2(20),
5 email varchar2(25),
6 constraint pk_people primary key (employee_id)
7 );
Table created.
SQL>
SQL> insert into people values (1, 'T', 'Kyte', 'YourName@q.com');
1 row created.
SQL>
SQL> insert into people values (2, 'S', 'Dillon', 'sdillon@q.com');
1 row created.
SQL>
SQL> insert into people values (3, 'C', 'Beck', 'clbeck@q.com');
1 row created.
SQL>
SQL> select * from people;
EMPLOYEE_ID FIRST_NAME LAST_NAME EMAIL
----------- --------------- -------------------- -------------------------
1 T Kyte YourName@q.com
2 S Dillon sdillon@q.com
3 C Beck clbeck@q.com
SQL>
SQL>
SQL> alter table people
2 add(
3 t_name varchar2(40),
4 st_name varchar2(15)
5 );
Table altered.
SQL>
SQL> select * from people;
EMPLOYEE_ID FIRST_NAME LAST_NAME EMAIL T_NAME ST_NAME
----------- --------------- -------------------- ------------------------- ---------------------------------------- ---------------
1 T Kyte YourName@q.com
2 S Dillon sdillon@q.com
3 C Beck clbeck@q.com
SQL>
SQL> drop table people;
Table dropped.
SQL>