return conn.ping();
return pg_query(env, conn, "SELECT 1") != null;
  public static boolean pg_ping(Env env,                                @Optional Postgres conn)  {    try {      if (conn == null)        conn = getConnection(env);      return conn.ping();    } catch (Exception ex) {      log.log(Level.FINE, ex.toString(), ex);      return false;    }  }