if ( $mode eq "add" ) {
 # print add page form
}
if ( $mode eq "save" ) {
 # save add form infos
}

##</code><code>##

print hidden( 'mode' , 'save' );

##</code><code>##

<input type="hidden" name="mode" value="add"  />

##</code><code>##

print hidden( 'mode' , 'save' );

##</code><code>##

<input type=hidden name=mode  value=save />

##</code><code>##

$query -> delete('mode');

$query -> delete_all();