12     private $db=null;  #use getdb() to access this.  variable in helper_plugin_linkcheck
50         if(!isset($this->db)){
51             if($file=$this->getdbfile()) $this->db=linkcheck_db($file);
52             else $this->db=false;
54         return $this->db;
83         $db=&$this->getdb();
87         $id_=$db->escapeString($id);
89         foreach(linkcheck_db_query($db,$query) as $row){
97             $urls_=array_map([$db,'escapeString'],$deleteurls);
101             $db->exec($query);
105             $db->exec($query);
110             $urls_=array_map([$db,'escapeString'],$newurls);
113             foreach(linkcheck_db_query($db,$query) as $row){
125 …$insertstmt = $db->prepare("INSERT OR IGNORE INTO linkcheck_cache(url,pages) VALUES (:url,:pages)"…
126         $updatestmt = $db->prepare("UPDATE linkcheck_cache SET pages=:pages WHERE url=:url");