Ordering by two custom fields values - wordpress

Question

I have custom post type called "lawyer" and I want to query lawyers ordered by custom field "surname" and then ordered by custom field "name". My query looks like this:
query_posts( array ( 'post_type' => 'lawyer', 'posts_per_page' => -1, 'meta_query' => array(array('key' => 'surname', 'orderby' => 'meta_value', 'order' => ASC), array('key' => 'name', 'orderby' => 'meta_value', 'order' => ASC) )) );
But it's not working. I get results, but they are not ordered the way I want them to. Any idea what is wrong here?

Answer 1

Don't use query_posts() ever.
Reference When should you use WP_Query vs query_posts() vs get_posts()?
You can do it by using WP_QUERY and adding filter to posts_orderby
function custom_orderby($orderby) {
global $wpdb;
return str_replace($wpdb->prefix.'postmeta.meta_value', 'mt1.meta_value, mt2.meta_value ASC', $orderby);
}
Then Prepare your arguments.
$args = array(
'post_type'=>'lawyer',
'orderby' => 'meta_value',
'meta_key' => 'surname',
'meta_query' => array(
array(
'key' => 'surname',
'value' => '',
),
array(
'key' => 'name',
'value' => '',
)
)
);
And add your custom order by filter just before the query execute.
add_filter('posts_orderby','custom_orderby');
$loop = new WP_Query( $args );
remove_filter('posts_orderby','custom_orderby');

Answer 2

Finally made it work with this code:
function double_meta_posts_orderby($orderby) {
remove_filter('posts_orderby', 'double_meta_posts_orderby');
global $wpdb;
return " {$wpdb->postmeta}.meta_value, mt1.meta_value";
}
$args = array(
'post_type'=>'lawyer',
'post_per_page' => -1,
'meta_query' => array(
array(
'key' => 'surname',
),
array(
'key' => 'name',
)
),
'orderby' => 'meta_value',
'order' => ASC,
);
add_filter('posts_orderby', 'double_meta_posts_orderby');
$loop = new WP_Query( $args );
// the Loop
while ($loop->have_posts()) : $loop->the_post();
...