How filter posts by Year on Wordpress

Question

How to filter posts by year, by a custom field?

$args = array(
    'post_type'   => 'movies',
    'showposts'   => '28',
    'meta_value' => array( 'release_date' =>  '2021-09-01', ),          );

Answer 1

You probably need something along the meta query lines: See WP_Meta_Query

$args = array(
              'post_type' => 'movies',
              'post_status' => 'publish',
              'posts_per_page' => -1,
              'orderby'   => 'release_date',
              'order'     => 'ASC',
              'meta_query'  => array(
                'relation' => 'AND',
                array(
                  'key'   => 'release_date',
                  'value'     => '2021-09-01',
                  'compare'   => '=',
                  'type' => 'DATE'
                ),
              )
            );

Answer 2

Just use the global $wpdb to execute your custom DB query.

It should be something like that:

SELECT p.ID, m.meta_value as post_year FROM wp_posts p INNER JOIN wp_postmeta m ON (p.ID = m.post_id and m.meta_key = 'release_date') WHERE p.post_type = 'movies' and 'publish' ORDER BY m.meta_value DESC;

And on the PHP side you may use something like code below:

global $wpdb;

$results = $wpdb->get_results( $query, 'ARRAY_A' );

Or use WP_Meta_Query . But i believe that it might be resolved as simple DB-request without extra helper classes.

if you know mysql well you will able to customize that request easily for your aims.

Wish you luck.