fix ido2db produces empty transactions

The patch works around instances where only the "baseline" set
of IDO data are submitted by core which, as there's no real data,
causes empty "BEGIN/COMMIT" transactions to be generated by ido2db.

Empirically, the largest such packet I saw was 47 bytes, with
others at 46 and 46 bytes.

fixes #4221

Conflicts:
	Changelog