Tag Archives: performance

Composite Indexes in Neo4j 4.0

Neo4j 4.0 has officially launched and folks are very excited about some of the new features including multiple graphs and schema based security. But you should also be excited about some of the more “quality of life” improvements in the product. One we will talk about today is the upgrade that composite indexes received.

Continue reading

Tagged , , , , , , , ,

Going Faster in 2020

Everybody loves benchmarks. Well let me rephrase that, everyone who publishes benchmarks loves the benchmark they publish. Nobody publishes benchmarks that make them look bad, it would be a terrible idea. But you my friend are in luck. I’m full of terrible ideas and today I’m going to publish some benchmarks that makes us look bad. Why? Because we are actively trying to improve this part of Neo4j and I want to experiment with some ideas and see what a ballpark theoretical limit should look like…and I’ll throw in some “inside baseball” about the graph database space from my point of view if you stick around until the end.
Continue reading

Tagged , , , , , , , ,

Getting the latest transactions

On Neo4j’s User Slack someone was having a bit of a hard time getting a query to return quickly. Their model had User Nodes and Transaction Nodes, and they wanted to get the last 25 transactions for a user. This particular user had millions of transactions and the query was taking forever. I’m going to show you how we can speed up the query and hopefully teach you a new modeling trick you can use in your graphs.

Continue reading

Tagged , , , , ,

Visualizing Activities

A few weeks ago I blogged about Activities in Neo4j, and we ended up with a way to recommend an activity to a user based on what sequence of activities they had done in the past. We also had a list of common sequences of activities, but they were a bit hard to digest. Today I’m going to show you how to visualize them so they make more sense.

Continue reading

Tagged , , , , , , , ,

Finding Fraud

It’s no secret that one of our hottest use cases lately has been Fraud Detection. A while back we did a webinar talking about some of the ways you could use Neo4j to fight fraud. Watch it, if you haven’t yet. Today I want to augment that webinar with some cypher queries. Let’s see how it works:
Continue reading

Tagged , , , , , , , , , , , ,

Parallel K-Hop Counts

As a foreigner I was a little perplexed the first time I went to IHOP. You are served a stack of pancakes 3-5 high. How do you eat them? Do you pour syrup over the top and cut down through all the layers and eat them that way… or do you unstack them, pour syrup over each one and eat one at a time? If you are American, you eat them stacked. If you see someone eat them one at a time, you know they are shape-shifting lizard people. But doesn’t that mean the bottom layers are dry and don’t get any butter or syrup on them? Well you would think, but Americans are an ingenious people and they found a way to fix that problem. More syrup, more and more, and then a bit more to be sure… and a side of bacon. Now that you know all about IHOP, let’s switch gears to KHOP. Let’s say you wanted to find out how many nodes there were k-hops away from a starting node. What would be the best way to do that?

Continue reading

Tagged , , , , , , , , ,

Vendor Benchmarks

How does the saying go? There are lies, damned lies, and benchmarks. I’ve already made my feelings about database vendor benchmarks known, but in case you missed it. They are complete fabrications. Never to be trusted, never ever. Never. But vendors love to do benchmarks, they love spreading fear, uncertainty and doubt instead of spending their time doing productive things like creating useful content that teaches people how to use their product. I wish I could just ignore this nonsense and focus on what really matters, like helping our customers to successful production rollouts, but alas, here we are.

Continue reading

Tagged , , , , , , ,

Calculating the best Rail Road paths in Neo4j

Did you know that Chicago is the most important railroad center in North America? Chicago has more lines of track radiating in more directions than from any other city. The windy city has long been the most important interchange point for freight traffic between the nation’s major railroads and it is the hub of Amtrak, the intercity rail passenger system. You may not realize it, but railroad tracks and graph theory have a history together. Back in the mid 1950s the US Military had an interest in finding out how much capacity the Soviet railway network had to move cargo from the Western Soviet Union to Eastern Europe. This lead to the Maximum Flow problem and the Ford–Fulkerson algorithm to solve it.

Continue reading

Tagged , , , , , , , , , , ,

Neo4j Stored Procedures for Devs that don’t know Java (yet)

When I joined Neo4j, I didn’t know how to write Java. I was a SQL developer who knew some Ruby and that’s about it. Luckily I had Michael Hunger, Stefan Armbruster, David Montag and others to help me out. I realize however that you may not be so lucky. So today I’m going to share with you a set of slides to help you start you on your journey of using the full power of Neo4j.
Continue reading

Tagged , , , , , , , , , ,

Dynamic Rule Based Decision Trees in Neo4j – Part 4

So far I’ve only showed you how to traverse a decision tree in Neo4j. The assumption being that you would either create the rules yourself from expert knowledge or via an external algorithm. Today we’re going to add an algorithm to build a decision tree (well a decision stream) right into Neo4j. We will simply pass in the training data and let it build the tree for us. If you are reading this part without reading parts one, two, and three, you should because this builds on what we learned along the way.

Continue reading

Tagged , , , , , , , , , , , , ,