Meta search dates

$meta_query = array(
	'relation' => 'AND',
	array(
		'key'     => 'dnl_event-start_time',
		'value'   => 'start',
		'compare' => '>',
		'type'    => 'DATETIME',
	),
	array(
		'key'     => 'dnl_event-start_time',
		'value'   => 'end',
		'compare' => '<',
		'type'    => 'DATETIME',
	),
);