How would you model for 'recent updates'?

[geronimo4j]

Hi I have a Neo4j graph where Users can create Posts and can also follow Movies or Shows or add these things to Lists.

With posts I can get the most recent Posts by Users followed other Users just by ordering by date and that's a single feed, but I am looking to create another feed that is more of a catch all.

It would show any time a User follows another User , or a User adds something to a List, or follows another User, etc.

For this I am interested in seeing how I might be able to structure the graph and these relationships to even be able to create a GraphQL query that can return this stuff, and a node/object type that could be returned.

Do I add properties to relationships between nodes and try to sort by those? If so, if I'm trying to return these 'updates', how would I be able to generate a list of all of the most recent relationships when they're all of different kinds (like :FOLLOWS, :LIST_HAS_MOVIE, etc.?

Essentially I want to say:

• User A is following User B
• User A is following List 7
• Return for User A when User B follows another user or List 7 has a movie or show added to it

I can't figure out the structure that might make sense here. Happy to clear anything up.

[david_allen]

These updates you want your users to make (someone followed someone, or someone added things to a list) -- these updates you are currently modeling as relationships, but your use case would probably benefit by "Reifying" these relationships into proper nodes.

Instead of:

(:User)-[:FOLLOWED { when: datetime() }]->(:User)
(:User)-[:CREATED { when: datetime() }]->(:Post)

Think about this:

(:User)-[:INITIATED]->(:Action { type: 'post', when: datetime() })-[:ON]->(:Post)
(:User)-[:INITIATED]->(:Action { type: 'follow', when: datetime() })-[:ON]->(:User)

Now how do you build a feed? Dead simple.

MATCH (u:User)-[:INITIATED]->(a:Action)-[]->(t:Target)
RETURN a.type, labels(t), a.when
ORDER BY a.when DESC

For much more information on why this might make sense, check this article, the "Reifying relationships" heading Graph Data Modeling: All About Relationships | by David Allen | Neo4j Developer Blog | Medium

[geronimo4j]

Hi @david.allen this sounds really interesting, but I'm curious how it might affect my other graphQL queries.

Say I'm just looking for followers, right now I just look for type User and call followers which is a list of Users with the :FOLLOWS relationship. It feels like direct relationships between Users and the other nodes could be stronger although I see the benefits of your approach. Definitely has me thinking.