TYPO3重新连接数据库

I have a quite long running command controller/scheduler job, accessing the database at the very end. With standard MySQL timeout settings it runs into a "MySQL Server has gone away". Increasing the timeout I can circumvent the error. However, I'd like to fix the problem. How can I reconnect to the db (TYPO3 7.6)?

I tried

$GLOBALS['TYPO3_DB']->connectDB();

but this did not work.

If the connection times out the state in TYPO3's DatabaseConnection::$isConnected is still set. You could try the following:

// isConnected() sends a ping and modifies internal $isConnected property
if (!$GLOBALS['TYPO3_DB']->isConnected()) {
  // re-connect to database if required
  $GLOBALS['TYPO3_DB']->connectDB();
}