title: getting parent key not found error in sql
body: <pre><code>insert into employees(employee_id,e_name,department_id)
  values (5, 'faizi', 6);
  </code></pre>
  
  <hr />
  
  <pre><code>insert into department(loc_id, d_name, department_id)
  values (11, 'bba',6);
  </code></pre>
  
  <p>I am getting the following error.  The departmentId is the primary key in the employees table and a foreign key in the department table.  Why am I getting this error?</p>
  
  <blockquote>
    <p>ORA-02291: integrity constraint (SYS.SYS_C003995) violated - parent key not found</p>
  </blockquote>