title: Oracle Conditional where clause
body: <p>is there any way to write query with following functionality, add where clause as a conditional way,</p>
  
  <pre><code>      select e.emp_id, emp.admin_user from employees e
  </code></pre>
  
  <blockquote>
    <p>if emp.admin != 'Y'</p>
    
    <p>then</p>
    
    <p>query run with where clause  </p>
    
    <p>else </p>
    
    <p>query run without where clause ?</p>
  </blockquote>