Category 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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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.

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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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Finding your neighbors using Neo4j

In Mr. Rogers’ Neighborhood, the question “Won’t you be my neighbor?” is an invitation for somebody to be close to you. In graphs, it’s an invitation to traverse. The closest neighbors of a node are those reachable by a single relationship hop, but we can also consider nodes two, three or more hops away our neighbors as well. How can we find them in Neo4j? Using the “star”:
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Offers with Neo4j

If you have started or are thinking about starting a Graph project, you ought to get in touch with me. I’ve been involved in hundreds of graph database backed projects and chances are I can point you in the right direction. It doesn’t cost anything to get on a goto meeting for an hour and talk about it. Contact me at max@neo4j.com to schedule it. If you are very serious and have a little budget allocated then I recommend you sign up for one of our bootcamps. You’ll be amazed at what we can accomplish together in a very short time. I’ll even make you a deal, if you sign up for a bootcamp and end up buying a commercial license, we’ll give you a week of professional services absolutely free.
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Scheduling Meetings with Neo4j

One of the symptoms of any fast growing company is the lack of available meeting rooms. The average office worker gets immense satisfaction to their otherwise mundane workday when they get to kick someone else out of the meeting room they booked. Of course that joy can be cut short (along with their career) once realizing some unnoticed VIP was unceremoniously kicked out. It’s not a super exciting use case, but today I’m going to show you how to use Neo4j to perform some scheduling gymnastics.
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Neo4j Geospatial Queries

When I was growing up, the Neo Geo was the high end gaming system around. It was however prohibitively expensive for most people… and definitely out of my price range. I grew up in a mobile home park in Union City, CA. Near the old drive in theater now long gone. It was also next to an industrial park in Hayward where a food truck would make the best burritos $3 could buy. A search for the best burritos in Union City would have missed this food truck gem. Geographic boundaries can be a problem when searching for things by specific places. To get around this problem, we tend to use latitude and longitude and then perform a radius or bounding box search. Today I want to present to you a hybrid approach using 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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