if logic in posts_where not working wordpress - php

Question

My if ( $filter == 'on' ) in the ugrestriction_filter function seems to not be working in this code when viewing a post. I'm executing this from functions.php It does work when viewing a page. How can I make this work?
Here's my code:
// Join metadata
function ugrestriction_join($join) {
global $wp_query, $wpdb;
$join .= "LEFT JOIN ($wpdb->postmeta) ON ($wpdb->posts.ID = $wpdb->postmeta.post_id) ";
return $join;
}
add_filter('posts_join', 'ugrestriction_join');
// Prevent duplicates
function ugrestriction_distinct( $where ) {
global $wpdb;
return "DISTINCT";
return $where;
}
add_filter( 'posts_distinct', 'ugrestriction_distinct' );
// Filter posts
function ugrestriction_filter( $where, $wp_query )
{
global $wpdb, $post, $current_user, $wp_query;
get_currentuserinfo();
$user_id = $current_user->ID;
$page_id = $wp_query->get_queried_object_id();
$post_id = $post->ID;
$meta_key1 = '_ugrestriction';
$meta_key1_value = 'on';
$postids=$wpdb->get_col( $wpdb->prepare(
"SELECT post_id FROM $wpdb->postmeta WHERE meta_key = %s AND meta_value = 'on'", "_ugrestriction"
) );
//$postids = array("70", "1", "2", "3");
if (in_array($post_id, $postids)) {
$filter = 'on';
} elseif (in_array($page_id, $postids)) {
$filter = 'on';
}
if ( $filter == 'on') {
$where .= " AND ($wpdb->postmeta.meta_key = '_ugrestriction' AND $wpdb->postmeta.meta_value = 'on' AND " . $wpdb->posts . " .post_author =". $user_id .")";
}
return $where;
}
add_filter( 'posts_where', 'ugrestriction_filter', 10, 2 );

Answer 1

From the documentation:
Certain functions which retrieve posts do not run filters, so the
posts_where filter functions you attach will not modify the query. To
overcome this, set suppress_filters to false in the argument array
passed to the function
Source
Have you tried this?