Oracelaltertable adds the primary key primarykeysql & gt; SQL & gt; createtableemp (empnonumber (4) notnull, & nbsp; 2 & nbsp; & nbsp;
SQL>
SQL> create table emp (empno number (4) not null,
2 ename varchar2 (10 ),
3 job varchar2 (9 ),
4 mgr number (4 ),
5 hiredate date,
6 sal number (7, 2 ),
7 comm number (7, 2 ),
8 deptno number (2 ));
Table created.
SQL>
SQL> insert into emp values (7369, 'Smith ', 'cler', 7902, to_date ('17-dec-1980', 'dd-mon-yyyy'), 800, null, 20 );
1 row created.
SQL> insert into emp values (7499, 'allen', 'salesman', 7698, to_date ('20-feb-1981 ', 'dd-mon-yyyy'), 1600,300, 30 );
1 row created.
SQL> insert into emp values (7521, 'ward ', 'salesman', 7698, to_date ('22-feb-1981', 'dd-mon-yyyy'), 1250,500, 30 );
1 row created.
SQL> insert into emp values (7566, 'Jones ', 'manager', 7839, to_date ('2-apr-1981', 'dd-mon-yyyy '), 2975, null, 20 );
1 row created.
SQL> insert into emp values (7654, 'martin ', 'salesman', 7698, to_date ('28-sep-1981', 'dd-mon-yyyy'), 1250,140 0, 30 );
1 row created.
SQL> insert into emp values (7698, 'bucke', 'manager', 7839, to_date ('1-may-1981 ', 'dd-mon-yyyy'), 2850, null, 30 );
1 row created.
SQL> insert into emp values (7782, 'clark', 'manager', 7839, to_date ('9-jun-1981 ', 'dd-mon-yyyy'), 2450, null, 10 );
1 row created.
SQL> insert into emp values (7788, 'Scott ', 'analyst', 7566, to_date ('09-dec-1982', 'dd-mon-yyyy'), 3000, null, 20 );
1 row created.
SQL> insert into emp values (7839, 'King', 'President ', null, to_date ('17-nov-1981', 'dd-mon-yyyy '), 5000, null, 10 );
1 row created.
SQL> insert into emp values (7844, 'turner ', 'salesman', 7698, to_date ('8-sep-1981', 'dd-mon-yyyy'), 1500, 0, 30 );
1 row created.
SQL> insert into emp values (7876, 'adams', 'cler', 7788, to_date ('12-jan-1983 ', 'dd-mon-yyyy'), 1100, null, 20 );
1 row created.
SQL> insert into emp values (7900, 'James ', 'cler', 7698, to_date ('3-dec-1981', 'dd-mon-yyyy '), 950, null, 30 );
1 row created.
SQL> insert into emp values (7902, 'Ford ', 'analyst', 7566, to_date ('3-dec-1981', 'dd-mon-yyyy '), 3000, null, 20 );
1 row created.
SQL> insert into emp values (7934, 'miller ', 'cler', 7782, to_date ('23-jan-1982', 'dd-mon-yyyy'), 1300, null, 10 );
1 row created.
SQL>
SQL>
SQL> create table emp_reg
2
3 * from emp;
SQL>
SQL> alter table emp_reg add constraint emp_pk primary key (empno );
Table altered.
SQL>
SQL>
SQL> drop table emp_reg;
Table dropped.
SQL> --