Storing text in Neo4j

Question

We're using Neo4J and liking it. We do all sorts of graphy things in it. However, some of what we do is not graphy. For example, we keep a log of all changes to a certain type of node:

(n)-[:CHANGE]->(c1)-[:CHANGE]->(c2) etc etc

This list of changes can get to be 20 or 30 c1 nodes long. While it looks weird, I don't have a real problem with it. (Of course, I am smarter now, and since each :CHANGE relationship has a date in it, I could porcupine all the c1 nodes right from n. But whatever.)

But what if I wanted to store large amounts of text, or images. Is there a problem with storing large amounts of data in a node? I could use a different database for these things, but this just increases the skill set required to run the business. And of course, joining data in two disparate databases is always a PITA.

So I need to worry about storing large amounts of text in a single property? Do I need to avoid creating logs in the way I did above?

Answer 1

Creating linked lists of events, whatever they may be, is fine. It'd even say it is graphy! We use this approach a lot, in the case of ChangeFeed for something similar to what you're doing.

In Neo4j, such a linked list is actually better than a "porcupine", because you have to traverse all the relationships anyway, if you're looking for all changes. But in the linked list case, you don't have to look at properties to order them. In fact, the best approach is a hybrid approach, like the TimeTree.

As for storing large amounts of text or images, Neo4j is not the best place for it. Another database would be best, especially if the volume of these is large ( > hundreds of thousands).

But if you do want to store them in Neo4j, one thing to keep in mind is that Neo4j will load all the properties of a node/relationship once a single property is accessed. So in order to achieve good performance even with text/images in Neo4j, I would store them in a node of their own. That way, you can only load them if you really need them, but not during regular traversals.

For example:

CREATE (b:BlogPost {title:'Neo4j Rocks', author:'Tony Ennis', date:".."})-[:HAS_BODY]->(:BlogPostBody {content:'..'})