Necessary to check for empty variable after validation and before saving data?
<p>Is it still necessary to check for empty variable after validation a form and before saving a data?</p>

<p>This step is somewhat unnecessary because if a user does not enter any input, the validation rule would definitely trigger an error. </p>

<p>However, I've seen comments from others saying that if user input gets sanitized it might return an empty variable. But how often do we get user who will enter pure XSS script that will only return an empty variable?</p>

<p>Anyone has any opinions on this? Thanks in advance.</p>
