Exclude Posts With Certain Tag

This snippet allows you to exclude posts tagged with a certain tag from the loop. It does not require the tag-id, but accepts the tag-name and resolves the name to the id that belongs to the tag for you.

Code Snippet:

// Query_Posts in your loop
      'tag__not_in' => array( get_tag_id_by_name('teaser') )

// The following function goes into your functions.php
function get_tag_id_by_name($tag_name) {
    global $wpdb;
    return $wpdb->get_var("SELECT term_id FROM ".$wpdb->terms." WHERE `name` =  '".$tag_name."'");

Posted in Conditional