_sku test

$meta_query = array(
	'relation' => 'AND',
	array(
		'key'     => '_sku',
		'value'   => '899 %',
		'compare' => 'LIKE',
	),
	array(
		'key'     => '_stock_status',
		'value'   => 'instock',
		'compare' => '=',
	),
);