Tag Archives: cypher

Modeling Events in Neo4j

No. Not modeling events, I’m talking about modeling events. Things that happen at different times typically in some known sequence. If you are a long time follower of my blog you know I love promoting the date property of an event into the relationship type to make use of Neo4j’s individual Node-RelationshipType partitioning to speed up my queries, but I’m going to show you something different today.
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Filtering Connected Dynamic Forms

Sometimes I contrast Neo4j against relational databases by saying Neo4j is more like a dynamic typed language, and relational databases are more like a static typed language. In Neo4j you don’t have Tables or table definitions, any property can be of any valid value (Java primitives, arrays of Java primitives as well as time and spatial types). Two nodes with the same Label can have completely different properties, and any key can be of any type for different nodes. So for example a User labeled node may have the “id” property be “xyz”, while the “id” property for a Location labeled node may be a spatial type… but another User labeled node may also have the “id” property be a number or an array of floats, or whatever. This kind of freedom can drive people crazy, but it can also be leveraged to make very dynamic applications easy.
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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.
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Mutual Fund Benchmarks with Neo4j

Just the other day I had a conversation with an Investment Risk Manager about one of the data problems his team was working on and he was wondering if Neo4j could help. Imagine you have about 20,000 mutual funds and etfs and you want to track how they measure up against a benchmark like say the returns of the S&P 500. I’m sorry did I say one? I meant all of them, let’s say 2,000 different benchmarks… and you want to track it every day, for a rolling 5 years period. So that’s 20,000 securities * 2000 benchmarks * 5 years * 252 trading days a year (on average)… or 50 billion data points. That’s a BIG join table if we were using a relational database. How can we efficiently model this in Neo4j?
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Bill of Materials in Neo4j

Where is da BOM? The above question asks, and the obvious answer is right in the middle of your organization. Nestled between Manufacturing, Design, Sales and Supply Chain. But I have a better answer. Your Bill of Materials should be in Neo4j. Today, I’ll show you why.
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Counting Nodes with Multiple Labels

We have over 6000 users in our #neo4j-users slack channel and get all kinds of requests. About a month ago Thomas Shields asked:

Should counting the set of things with 2 labels really take so long? I’ve got 48M nodes with LabelA and LabelB and the query `MATCH (n:LabelA:LabelB) RETURN COUNT(n)` is taking 80-90 seconds

Let’s see what’s going on by creating a small version of his graph. We will create 1M nodes of LabelA, then 1M nodes with both LabelA and LabelB, and then 1M nodes with just Label B:
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Finding Triplets with Neo4j

A user had an interesting Neo4j question on Stack Overflow the other day:

I have two types of nodes in my graph. One type is Testplan and the other is Tag. Testplans are tagged to Tags. I want most common pairs of Tags that share the same Testplans with a Tag having a specific name. I have been able to achieve the most common Tags sharing the same Testplan with one Tag, but getting confused when trying to do it for pairs of Tags.

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Using a Cuckoo Filter for Unique Relationships

We often see a pattern in Neo4j applications where a user wants to create one and only one relationship between two nodes. For example a User follows another User on a social network. We don’t want to accidentally create a second follows relationship because that may create errors such as duplicate entries on their feed, or errors unfollowing or blocking them, or even skew recommendation algorithms. Also it is just plain wasteful, and while an occasional duplicate relationship won’t be a big deal, millions of them could.

So how do we deal with this?
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Neo4j is faster than MySQL in performing recursive query

5mysql

A user on StackOverflow was wondering about the performance between Neo4j and MySQL for performing a recursive query. They started with Neo4j performing the query in 240 seconds. Then an optimized cypher query got them down to 40 seconds. Then I got them down to…
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Writing a Cypher Stored Procedure

luke-cage-jidenna

I’ve been so busy these last 6 months I just finally got around to watching Luke Cage on Netflix. The season 1 episode 5 intro is Jidenna performing “Long live the Chief” and it made me pause the series while I figured out who that was. I’m mostly a hard rock and heavy metal guy, but I do appreciate great pieces of lyrical work and this song made me take notice. Coincidently on the Neo4j Users Slack (get an invite) @sleo asked…
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