Wordpress，pre_get_posts 中有多个 meta_key

Question

是否可以添加两个 meta_key's在 pre_get_posts ?

我当前的查询

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

添加此

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

编辑
好的，我找到了这个解决方案( 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' => '>'
        )
    )
);

但它不起作用，有什么想法有什么问题吗？

$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

要将这两部分结合起来，您可以尝试以下操作:

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',          ''               );
    }
});

看来您错过了 compare参数并使用 order和 orderby参数位置错误。我不确定您为什么要重置搜索参数。

生成的 SQL 查询将类似于:

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