public function select_db($db_name)
{
$this->connect();
$sql = "USE {$db_name}";
$rid = $this->logReq(__METHOD__, $sql);
try {
$r = $this->link->exec($sql);
$this->logReqEnd($rid);
return true;
} catch (\PDOException $e) {
Db::debug($e, $sql);
}
}
