query to get all posts and associated categories from Wordpress database

gistfile1.php

    $all_posts = $wpdb->get_results("
       SELECT wp_posts.ID,wp_posts.post_date,wp_posts.post_title,wp_posts.post_name,
       wp_terms.name,wp_terms.slug,wp_term_taxonomy.description
       from wp_posts
          join wp_term_relationships on wp_posts.ID = wp_term_relationships.object_id
          join wp_terms on wp_term_relationships.term_taxonomy_id = wp_terms.term_id
          join wp_term_taxonomy on wp_term_relationships.term_taxonomy_id = wp_term_taxonomy.term_taxonomy_id
       WHERE wp_posts.post_status = 'publish'
       ORDER BY wp_terms.slug,wp_posts.ID;
    ", ARRAY_A);