title: How to assing a value to a variable with NULL value in SELECT INTO statement?
body: <p>I have a query:</p>
  
  <pre><code>DECLARE
    id_tmp number;
  BEGIN
    select id into id_tmp from ...;
  END;
  </code></pre>
  
  <p>So there is a possibility that there is no <code>id</code> selected by query. And I have got an error:</p>
  
  <blockquote>
    <p>ORA-01403: data not found</p>
  </blockquote>
  
  <p>How to handle this and assign <code>id_tmp</code> with <code>NULL</code>?</p>