static public function exists( $tagID, $keyword, $parentID )
    {
        $db = eZDB::instance();
        $sql = "SELECT COUNT(*) AS row_count FROM eztags, eztags_keyword
                WHERE eztags.id = eztags_keyword.keyword_id AND
                eztags.parent_id = " . (int) $parentID . " AND
                eztags.id <> " . (int) $tagID . " AND
                eztags_keyword.keyword LIKE '" . $db->escapeString( $keyword ) . "'";

        $result = $db->arrayQuery( $sql );

        if ( is_array( $result ) && !empty( $result ) )
        {
            if ( (int) $result[0]['row_count'] > 0 )
                return true;
        }

        return false;
    }