Table Oracle PLSQL

SQL> --Check Constraints
SQL>
SQL> create table employee
  2       ( employee_id      number,
  3       last_name          varchar2(30),
  4       first_name         varchar2(30),
  5       department_id      number,
  6       salary             number CHECK(salary < 100000));
Table created.
SQL>
SQL>
SQL> drop table employee;
Table dropped.
SQL> --