How to check in the meta_query parameter if there is / is not data that is stored as an array?

Question

WordPress

Good day, tell me, my WP_Query( $args ) request is formed depending on the parameters of different meta fields, everything is simple there ( comparison by values ​​or range ), but I can’t figure out how to check the presence or absence of an array in an arbitrary field?

My NOT working version:

$args['meta_query']['relation'] = 'AND';
if(empty($photo_search)==FALSE) {
                        switch ($photo_search) {
                            case 1: $photo_search = 'EXISTS'; break;
                            case 2: $photo_search = 'NOT EXISTS'; break;
                        }
                        $args['meta_query'][] = array(
                            'key' => 'photo',
                            'value' => $photo_search,
                            'type' => 'NUMERIC'
                        );
                    }

The custom field itself is filled with similar information (a field with galleries, image IDs are stored):

Array
(
[0] => 28919
[1] => 28921
[2] => 28922
[3] => 28923
[4] => 28924
[5] => 28925
[6] => 28926
[7] => 28927
[8] => 28928
)

Answer 1

As an option: we take the value of arbitrariness, and check it through is_array ()

<?php
$yes = array('это', 'массив');
echo is_array($yes) ? 'Массив' : 'Не массив';
echo "\n";
$no = 'это строка';
echo is_array($no) ? 'Массив' : 'Не массив';
?>