How to merge records by custom field?

Question

WordPress

Hello. I want to get the following structure on the page:
Comedy
Title 1, Title 2, Title 3
Tragedy
Title 1, Title 4, Title5
Documentary
Title 2, Title 4, Title5
and so on.
Comedy, Tragedy and Documentary are arbitrary fields of records
. I cannot make them headings, as headings will be displayed differently in layout.
It is necessary to deduce Arbitrary fields.
My code

<?php
class Cinema_Walker_Category extends Walker_Category {
  
   function start_el( &$output, $category, $depth = 0, $args = array(), $id = 0 ) {
    $name = $category->name;
    $category_id = $category->term_id;
    $count = $category->count;
    $output .= $name;
    $myPosts = get_posts(array(
      'category'  => $category->term_id,
      'order' => 'ASC',
      'orderby' => 'meta_value',
      'meta_query' => array(
                array( 
                  'key' => 'cinema'
                )
              )			
 		));

      foreach($myPosts as $newPosts){
        $newText = $newPosts->post_title;
        $post_id = $newPosts->ID;
        $permalink = get_permalink($post_id);
        $thumb = get_the_post_thumbnail_url( $post_id, 'medium' );
        $meta_values = get_post_meta( $post_id, 'cinema', true );
        $string = '';

        switch ($meta_values){
          case 0:
            $string = 'драма';
            break;
          case 1:
            $string = 'комедия';
            break;
          case 2:
            $string = 'трагедия'; 
            break;
          case 3:
            $string = 'документалка';
            break;
        };
    
        $output .= '<span class="floor-category__floor-name">'.$string.'</span><span>'.$newText.'</span>';
              
      }			


  }
}
?>

The output is as follows:
Comedy
Title 1,
Comedy
Title 2,
Comedy
Title 3
, and so on.
This is how I understand it, because I'm in a cycle. How can I combine records by custom field - cinema?

Answer 1

Well, I see several ways. One of them is to sort the selection by the cinema field, then only dramas will go first, then comedies, etc. Well, then in the foric where $output is formed, form the necessary output. Toist first we display the names of the genre, then the name of the films. And next time display the name of the genre only if it has changed. I think this will be the most painless option.
Change the query to the following:

$myPosts = get_posts(array(
      'category'  => $category->term_id,
      'order' => 'ASC',
      'orderby' => 'meta_value',
      'meta_key' => 'cinema',
      'meta_query' => array(
                array( 
                  'key' => 'cinema'
                )
              )			
 		));

Added only 'meta_key' => 'cinema', Although you specified the key in meta_query, I'm not sure if it works that way.
Well, when forming $output:

$prev_value = -1;
    if ($meta_values !=  $prev_value )  {
        $prev_value = $meta_values;
         $output = rtrim($output,', '); // Удалям последнюю запятую
         $output .= '<br><span class="floor-category__floor-name">'.$string.'</span><br>'
    }
    $output .= '<span>'.$newText.'</span>, '

Something like this, it should work +/-

Answer 2

An arbitrary field .. it seems to be intended for another,
but the conclusion .. before it was solved like this

SELECT * FROM $wpdb->posts
LEFT JOIN $wpdb->postmeta ON($wpdb->posts.ID = $wpdb->postmeta.post_id)
LEFT JOIN $wpdb->term_relationships ON($wpdb->posts.ID = $wpdb->term_relationships.object_id)
LEFT JOIN $wpdb->;term_taxonomy ON($wpdb->term_relationships.term_taxonomy_id = $wpdb->term_taxonomy.term_taxonomy_id)
WHERE $wpdb->term_taxonomy.term_id = 1,2,3
AND $wpdb->term_taxonomy.taxonomy = 'category'
AND $wpdb->posts.post_status = 'publish'
AND $wpdb->postmeta.meta_key = 'paragraf'
ORDER BY $wpdb->postmeta.meta_value ASC

I don't know about the new version.

Answer 3

The problem is that I can't exit the foreach loop(