Epoch fields

An epoch identifies one inventory and the deltas and monitor rows that follow it, for one device and topic.

Field	Type	Unit	Meaning
sparklogs.epoch.id	string		Globally unique inventory epoch ID. Parts and subsequent changes share this ID.
sparklogs.epoch.prev_id	string		Previous epoch ID for this agent and topic. Absent for the first epoch or after stored state was cleared.
sparklogs.epoch.seq	integer	count	Epoch sequence for this agent and topic, starting at 1. It can repeat after a crash or state reset; use the epoch ID for identity.