Wordpress, several meta_key in pre_get_posts

Question

can I add two meta_key's in pre_get_posts ?

my current request

 $query->set('s', '' ); $query->set( 'meta_key', 'cat_adresse_stadtteil' ); $query->set( 'meta_value', array('charlottenburg', 'wilmersdorf', 'schmargendorf') ); 

add this

 $query->set('orderby','meta_value_num'); $query->set('meta_key', 'rank'); $query->set('order', 'ASC'); 

EDIT
Ok, I found this solution ( link # example 2)

 $args = array( 'numberposts' => -1, 'post_type' => 'event', 'meta_query' => array( 'relation' => 'AND', array( 'key' => 'location', 'value' => 'Melbourne', 'compare' => '=' ), array( 'key' => 'attendees', 'value' => 100, 'type' => 'NUMERIC', 'compare' => '>' ) ) ); 

but it doesn’t work, any ideas what is wrong?

 $query->set('meta_query',array( array( 'key' => 'cat_adresse_stadtteil', 'value' => array('charlottenburg', 'wilmersdorf', 'schmargendorf'), ), array( 'key' => 'rank' 'orderby' => 'meta_value_num', 'order' => 'ASC' ) ) ); 

Answer 1

To combine the two parts, you can try the following:

 add_action( 'pre_get_posts', function( $q ) { // Only modify the main query on the front-end: if( ! is_admin() && $q->is_main_query() ) { $meta_query = array( array( 'key' => 'cat_adresse_stadtteil', 'value' => array('charlottenburg', 'wilmersdorf', 'schmargendorf'), 'compare' => 'IN', ), ); $q->set( 'meta_query', $meta_query ); $q->set( 'meta_key', 'rank' ); $q->set( 'orderby', 'meta_value_num' ); $q->set( 'order', 'ASC' ); $q->set( 's', '' ); } }); 

It looks like you are missing the compare parameter and use the order and orderby in the wrong place. I'm not sure, but why did you reset the search option.

The generated SQL query will look something like this:

 SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts INNER JOIN wp_postmeta ON (wp_posts.ID = wp_postmeta.post_id) INNER JOIN wp_postmeta AS mt1 ON (wp_posts.ID = mt1.post_id) WHERE 1=1 AND wp_posts.post_type IN ('post', 'page', 'attachment' ) AND (wp_posts.post_status = 'publish' OR wp_posts.post_author = 1 AND wp_posts.post_status = 'private') AND (wp_postmeta.meta_key = 'rank' AND (mt1.meta_key = 'cat_adresse_stadtteil' AND CAST(mt1.meta_value AS CHAR) IN ('charlottenburg','wilmersdorf','schmargendorf')) ) GROUP BY wp_posts.ID ORDER BY wp_postmeta.meta_value+0 ASC LIMIT 0, 10 

Answer 2

You can convert this request to pre_pget_posts:

 $meta_query_args = array( 'relation' => 'AND', // "OR" array( 'key' => '_my_custom_key', 'value' => 'Value I am looking for', 'compare' => '=' ), array( 'key' => '_your_min_model_key', 'value' => 1453, 'compare' => '>' ), array( 'key' => '_your_max_model_key', 'value' => 1923, 'compare' => '<' ) ); $meta_query = new WP_Meta_Query( $meta_query_args ); 

And compare the parameters:

 compare (string) - Operator to test. Possible values are '=', '!=', '>', '>=', '<', '<=', 'LIKE', 'NOT LIKE', 'IN', 'NOT IN', 'BETWEEN', 'NOT BETWEEN', 'EXISTS' (only in WP >= 3.5), and 'NOT EXISTS' (also only in WP >= 3.5). Values 'REGEXP', 'NOT REGEXP' and 'RLIKE' were added in WordPress 3.7. Default value is '='.