How does a relational database work

databases

How does a relational database work” is an excellent (lengthy, technical, but simply written and well explained) article on some of the most important bits inside the relational database.  It’s somewhat of a middle ground between a theoretical database discussion in college and vendor-specific documentation of a database engine.

Though the title of this article is explicit, the aim of this article is NOT to understand how to use a database. Therefore, you should already know how to write a simple join query and basic CRUD queries; otherwise you might not understand this article. This is the only thing you need to know, I’ll explain everything else.

I’ll start with some computer science stuff like time complexity. I know that some of you hate this concept but, without it, you can’t understand the cleverness inside a database. Since it’s a huge topic, I’ll focus on what I think is essential: the way a database handles an SQL query. I’ll only present the basic concepts behind a database so that at the end of the article you’ll have a good idea of what’s happening under the hood.

Whether you are a young programmer or an experienced DBA, I think, you’ll still find something in there which you either didn’t know or didn’t think about in this particular way.   Even if you know all this stuff, it’s a good memory refresher.

Strongly recommended!

A Curated List of Tech Podcasts

It’s been a few month since I reviewed my podcast subscriptions.  Driving over 150 kilometers every working day gives me plenty of time to readjust my tastes and preferences.  Just doesn’t leave me too much time to actually do something about it.

Podcasts are easy to subscribe to.  Once you find the ones you like.  Finding the ones you like takes forever though.  Here’s where WP Tavern’s post “Awesome Geek Podcasts: A Curated List of Tech Podcasts” comes in handy.  Cause it provides not one, but two lists of podcasts:

  1. The best WordPress podcasts ultimate list
  2. A curated list of Awesome Geek Podcasts.

And while I’m familiar with many on that list, there’s a tonne of those that I haven’t heard, or heard about.

Any other recommendations?

Exceptions and Errors in PHP 7

An Exceptional Change in PHP 7.0” blog post describes nicely what are the changes to exceptions and error handling in the upcoming PHP 7.  Among simple descriptions, there is this reference chart:

\Throwable
├── \Exception (implements \Throwable)
│   ├── \LogicException (extends \Exception)
│   │   ├── \BadFunctionCallException (extends \LogicException)
│   │   │   └── \BadMethodCallException (extends \BadFunctionCallException)
│   │   ├── \DomainException (extends \LogicException)
│   │   ├── \InvalidArgumentException (extends \LogicException)
│   │   ├── \LengthException (extends \LogicException)
│   │   └── \OutOfRangeException (extends \LogicException)
│   └── \RuntimeException (extends \Exception)
│       ├── \OutOfBoundsException (extends \RuntimeException)
│       ├── \OverflowException (extends \RuntimeException)
│       ├── \RangeException (extends \RuntimeException)
│       ├── \UnderflowException (extends \RuntimeException)
│       └── \UnexpectedValueException (extends \RuntimeException)
└── \Error (implements \Throwable)
    ├── \AssertionError (extends \Error)
    ├── \ParseError (extends \Error)
    └── \TypeError (extends \Error)

Very handy!