Q: get meta_key out from ACF repeater field Is it possible to loop through wordpress posts by a repeater fields content?
I have a event where you can add events through a repeater field (ACF) and I would like to show all dates for each event.
How do I do that?

A: Yes, you can use a meta_query to identify posts with that key and then loop through the repeater fields. It should look something like below.
ACF Repeater Fields
$args = array(   
    'meta_query' => array(
        array(
            'key'     => 'event_date',    //Or whatever your        
            'compare' => 'EXISTS',
        ),
    ),
);
// The Query
$query = new WP_Query( $args );

// The Loop
if ( $query->have_posts() ) {
    while ( $query->have_posts() ) {

       // check if the repeater field has rows of data
       if( have_rows('repeater_field_name') ){

           // loop through the rows of data
           while ( have_rows('repeater_field_name') ) : the_row();

              // display a sub field value
              the_sub_field('sub_field_name');

           endwhile;

       else {

       // no rows found

      }
    }
} else {
    // no posts found
}

// Restore original Post Data
wp_reset_postdata();

