Tag Archives: nosql

Building a Dating site with Neo4j – Part Seven

Now it is time to create the timeline for our users. Most of the time, the user wants to see posts from people they could High Five in order to elicit a conversation. Sometimes, they want to see what their competition is doing and what kind of posts are getting responses… also who they can low five. I don’t think they don’t want to see messages from people who are not like them and don’t want to date them but I could be wrong.
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Building a Dating site with Neo4j – Part Five

You ever eaten at a “Fusion Cuisine” type of restaurant? It’s a bit of a gamble. Personally I’m always up for eating just about anything… except Pho. That stuff messes me up. But back to fusion cuisine. I think my favorite is Indian and Mexican. Take your favorite Indian dish, wrap that in the warm embrace that is a burrito tortilla, heaven. Well, just about anything wrapped in a burrito is perfect. Why am I taking about Fusion and Wrapping stuff? Well, today we are going to add Auto Complete into our Dating Site, but before we can do that I need to talk to you about Neo4j’s Fusion Indexes and how they wrap the Lucene Indexes as well as our generation-aware B+tree (GB+Tree) indexes.
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Building a Dating site with Neo4j – Part One

You might have already heard that Facebook is getting into the Dating business. Other dating sites have been using graphs in the past and we’ve looked at finding love using the graph before. It has been a while though, so let’s return to the topic making use of the new Date and Geospatial capabilities of Neo4j 3.4. I have to warn you though that I’ve been with Helene for almost 15 years and missed out on all this dating site fun, what I do know I blame Colin for it and some pointers from the comments section of this blog post.
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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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Dynamic Rule Based Decision Trees in Neo4j – Part 2

A couple of weeks ago I showed you how to build a dynamic rule based decision tree in Neo4j. It was pretty simple and used an Expression Evaluator to determine if a set of parameters in an expression was true or false. Based on that answer it decided where to go.

But what if we had more than just true or false? What if we wanted to make our Rule nodes have more than 2 options? Today I am going to show you how to do just that… but please make sure you have read part 1 already.

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Neptune and Uranus

Last year Microsoft announced “Cosmos DB”, a multi-modal database with graph support. I think multi-modal databases are like swiss army knifes, they can do everything, just not very well. I imagine you would design it to be as good as it can be at its main use case while not losing the ability to do other things. So it’s neither fully optimized for its main thing, nor very good at the other things. Maybe you can do pretty well with two things by making a few compromises, but if you try to do everything…it’s just not going to work out.

Can you imagine John Rambo stalking his enemies with an oversized swiss army knife? Here, let me help with the mental image:
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Dynamic Rule Based Decision Trees in Neo4j

A few posts ago I showed you how to build a Boolean Logic Rules Engine in Neo4j. What I like about it is that we’ve pre-calculated all our potential paths, so it’s just a matter of matching up our facts to the paths to get to the rule and we’re done. But today I am going to show you a different approach where we are going to have to calculate what is true as we go along a decision tree to see which answer we get to.

Yes, it will be a bit slower than the first approach, but we avoid pre-calculation. It also makes things a bit more dynamic, as we can change the decision tree variables on the fly. The idea is to merge code and data into one, to gain the benefit of agility.

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Adding gRPC to Neo4j

You are probably sick of me saying it, but one of the things I love about Neo4j is that you can customize it any way you want. Extensions, stored procedures, plugins, custom indexes, custom apis, etc. If you want to do it, then you can do it with Neo4j.

So the other day I was like what about this gRPC thing? Many companies standardize their backend using RESTful APIs, others are trying out GraphQL, and some are using gRPC. Neo4j doesn’t support gRPC out of the box, partially because we have our own custom binary protocol “Bolt”, but we can add a rudimentary version of gRPC support quite easily.
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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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Work Order Management with Neo4j

I look terrible in a bikini (take my word for it) but I’d love me a Lamborghini. However, in order to afford nice things, we need to do as the song says and get to work…and we need to manage and prioritize that work somehow. Today, I’m going to show you how to build part of a work order management system with Neo4j.

I’m going to build an evented work order model. So let’s say our Order gets created, then based on what it is, pieces of Work need to happen. This work is performed by some Provider (whether internal or external) and that work can be broken down into Tasks that have dependencies on Events that have occurred. How would this look like in the graph? Glad you asked:
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