Query Posts based on custom field value

Question

Currently building a site and need to create a 'Schedule' to display a Presenter that is on air at a particular time.

Using ACF plugin to enter a time that the presenter goes on air which saves the custom field value as a timestamp.

For some reason, I cant get the query to display the presenter that is on air at a certain time. It seems to just show the presenter with the highest timestamp value when compared to the current time timestamp. A simplified version of the code is below.

<?php $args = array(
    'post_type' => 'presenter',
    'posts_per_page' => '1',
    'meta_key' => 'on_air',
    'orderby' => 'meta_value_num',
    'order' => 'DESC'

);


$airquery = new WP_Query( $args ); ?>

<?php if ( $airquery->have_posts() ) : while ( $airquery->have_posts() ) : $airquery->the_post(); ?>

    <?php
        $now = strtotime(date('d-m-Y H:i:s')); // get current timestamp
        $stored_value = get_field('on_air');   // The saved post timestamp comparing to current timestamp
    ?>

    <?php if( $now > $stored_value )
        {
            echo the_title();
        }
    ?>

<?php endwhile; endif; wp_reset_postdata(); ?>

As you can see, i'm querying the posts in the post type, and want to order by meta value, which also doesnt seem to be working.

All I get returned is the post with the greatest timestamp value above the current timestamp.

All very strange. Dont know wether I need to somehow get the value of all the posts and then compare the $stored_value to the $now or not?

Any help would be great!

Answer 1

Why not pull the post you need, rather than pull a post and then check the value of the meta key?

$now = strtotime(date('d-m-Y H:i:s')); // get current timestamp

$args = array(
    'post_type' => 'presenter',
    'posts_per_page' => '1',
    'order' => 'DESC',
    'meta_query' => array(
        array(
            'key'     => 'on_air',
            'value'   => $now,
            'compare' => '>=',
        ),
    ),
);