How to modify the query to exclude posts by slug?

Question

How can I modify my query in order to exclude certain posts by slug? Is it possible?

query_posts(array('category_name' => 'Mycat', 'posts_per_page' => -1));

Ty

Answer 1

You can get the post ID from the slug with the url_to_postid() function:

$ID = url_to_postid(slug);

then just exclude the ID from your query:

query_posts(array('category_name' => 'Mycat', 'posts_per_page' => -1, 'post__not_in' => $ID ));

You can create an array of post IDs if you need to exclude multiple pages.

Answer 2

Do not use query_posts()!. Filter pre_get_posts instead *.

<?php
function wpse59617_filter_pre_get_posts( $query ) {
    // Only modify the main query
    if ( ! $query->is_main_query() ) { return $query; }
    // Get the ID of the post to exclude
    $slug = 'some-post-slug';
    $post_id = url_to_postid( $slug );
    // Modify the query
    $query->set( 'category_name', 'Mycat' );
    $query->set( 'post__not_in', $post_id );
    $query->set( 'posts_per_page', '-1' );
    // Return the modified query
    return $query;    
}
add_filter( 'pre_get_posts', 'wpse59617_filter_pre_get_posts' );
?>

* No, really: don't use query_posts(). Here's why.