SOLID Principles – Revisited

I recently rewrote an article on APIE, an article I originally wrote over 2 years ago. Now I am going to rewrite another article I wrote 2 years ago on the SOLID principles.

My views on the SOLID principles, have stayed largely the same, however my knowledge of these principles has matured. This hopefully means, I’ll be able to explain each principle in greater detail and be a lot more concise on each subject. I also like to think my writing style has matured and so I’m able to express myself better with less waffling, which is always a plus.

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What is APIE – Revisited

You’ve probably heard of APIE. If you haven’t, the most basic explanation is, “APIE is an acronym for the 4 paramount concepts within OOP, namely abstraction, polymorphism, inheritance and encapsulation.”

Each of these concepts is a huge discussion point in its own right, then there’s how they all fit together to form OOP. Many people have written multi-hundred page documents and book explaining these principles in depth and how to make use of them within different programming languages. Needless to say, I’m not going into that detail and I’m solely going to be discussing the language agnostics. By the end of this article, I hope to have explained each of the four concepts, covering a mix of what they are; how you should make use of them and how they all work together to keep you your code clean and human friendly.

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MongoDB – Part 10 – Internals and Final Thoughts

It’s taken me a year to write this MongoDB series, admittedly I have had a lot of down time, but this is the finale. One thing I’ve not given much explanation too, is the internals of MongoDB and how it works under, that what we’ll be covering here.

The main internals I want to cover are, how Mongo actually manages it write concerns using locks and how journaling works. After that, I’ll probably ramble on for a bit and have a big emotional climax.

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MongoDB – Part 9 – Deployments

Welcome back. Deploying MongoDB isn’t difficult, but there are a tonne of tricks you can use to really optimise your database. That’s what were going to be covering in this post.

I’m not going to be covering how to create clusters as I already covered that in part 5 of the series – Sharding. I’m not even going to discuss provisioning solutions like Puppet, Chef, Ansible etc. What I am going to discuss however, is a collection of system choices that need to be thought, about when creating your cluster. So let’s get started.

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