Prerequisite: Create Table

    create table employees (
        id NUMBER primary key,
        name VARCHAR2(100) not null
    );
    insert into employees(id,name) values (1,'Naresh');
    insert into employees(id,name) values (2,'Siva');

Create Sequence ( To Generate employee id automatically )

     CREATE SEQUENCE employees_id_seq START WITH 1 INCREMENT BY 1;

     insert into employees(id,name) values ( employees_id_seq.nextval, 'Naresh');
     insert into employees(id,name) values (employees_id_seq.nextval,'Siva');

Sequence Value

• To get next value.

  select employees_id_seq.nextval from dual;

• To get current value.

  select employees_id_seq.currval from dual;

Drop sequence

 drop table employees_id_seq;