Segments

A real-time segment is an always-on audience defined over a profile collection. Rather than a query you run to produce a list, a real-time segment is a predicate that Amperity evaluates continuously: as inbound events change a profile, Amperity re-evaluates the segment for that profile and adds or removes it. A real-time segment is a dynamically maintained audience, not a point-in-time query result. It is also called an always-on segment.

Real-time segments and database segments

Real-time segments and database segments are different objects, and Amperity manages them separately:

• A real-time segment is a predicate bound to a profile collection. Its membership is maintained continuously, in real time, as the collection’s profiles change.

• A database segment is a query bound to a database. Its membership is produced by running that query as a batch job.

Use a real-time segment when membership has to reflect a customer’s most recent activity the moment it happens–for example, to drive a real-time journey. Use a database segment for audiences built from your customer 360 database on a scheduled or on-demand basis.

How membership is maintained

A real-time segment’s predicate is written in Amperity’s expression language and evaluated against each profile in the bound collection. As events update a profile, Amperity re-evaluates the predicate for that profile: a profile that newly satisfies it enters the segment, and a profile that no longer satisfies it exits. These entries and exits are the signal that drives real-time journeys–a customer entering a segment is what starts them on a journey.

You can read a segment’s current membership–the profiles that belong to it right now–through the Real-time API.

Backfill and membership state

When you create a real-time segment, or change its definition, Amperity backfills its membership by evaluating the collection’s existing profiles against the predicate. Backfill has a status of its own: pending, in progress, complete, or paused.

A segment’s member count and its backfill status are distinct. In particular, a membership count shown as a dash is not the same as a count of zero:

• A dash means membership has not been computed yet–for example, a backfill that has not started.

• A 0 means membership has been computed and the segment has no members.

Reading a segment’s state returns the backfill status separately from the member count, so you can tell “not computed yet” apart from “computed and empty.”