- connect(this, SIGNAL(destroyed()), connection, SLOT(deleteLater()));
- connect(currentThread, SIGNAL(destroyed()), connection, SLOT(deleteLater()));
- connect(connection, SIGNAL(destroyed()), this, SLOT(connectionDestroyed()));
+ connect(this, &QObject::destroyed, connection, &QObject::deleteLater);
+ connect(currentThread, &QObject::destroyed, connection, &QObject::deleteLater);
+ connect(connection, &QObject::destroyed, this, &AbstractSqlStorage::connectionDestroyed);