Hey,
This not work for the NULL case.
You can use var_dump(get_field( 'exclude_post' ));
to test.
<?php
$args = array(
'post_type' => 'post',
'posts_per_page' => -1,
'meta_query' => array(
'relation' => 'OR',
array(
'key' => 'exclude_post',
'value' => '0',
'compare' => '='
),
array(
'key' => 'exclude_post',
'compare' => 'NOT EXISTS'
)
)
);
$query = new WP_Query( $args );
if ( $query->have_posts() ) :
while ( $query->have_posts() ) :
$query->the_post();
the_title();
endwhile;
wp_reset_postdata();
endif; ?>