Clarification on EventSeries vs SessionSeries

[matthew-inamdar]

I've read through the developer documentation on https://developer.openactive.io/ but I'm still struggling to understand the difference between an EventSeries and SessionSeries.

Can I please get some clarification on what distinction is?

Thanks in advance,
Matt

[matdavies]

Hi Matt,

I think this is probably the best page to define the relationship between ScheduledSession, SessionSeries and EventSeries:

https://developer.openactive.io/publishing-data/data-feeds/types-of-feed

I think the key differentiator is probably this:

For large providers with many events that are described identically but occur in the same location or in different locations, an EventSeries should be used to group these together. This avoids seemingly duplicate search results from a single provider.

And additionally:

For systems targeting small providers, the ScheduledSession may be embedded in the SessionSeries or visa versa.
For systems targeting large providers or small providers with high volumes of sessions, the ScheduledSession is highly recommended to be provided in a separate feed to the SessionSeries. This will reduce data transfer volumes significantly.
The EventSeries is unlikely to change frequently enough compared with the SessionSeries to warrant its own feed, and so can usually be embedded in the SessionSeries.

This section also contains links to example feeds showing both EventSeries and SessionSeries feeds.