Blog
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Book Review: The Undercover Economist Strikes Back
In order to get an undergraduate degree from MIT, at least when I was there, you needed to take a certain number of humanities and social-science courses. This was to stop you from coming out a complete one-dimensional student; the idea was that rounding out your education with knowledge from other fields was good for…
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Turning a PostgreSQL array to rows
I’ve spent the last few blog posts in this series talking about PostgreSQL’s arrays — how to create them, query them, and even create them with the ARRAY function. But there are cases in which I would like to do the opposite — turn a PostgreSQL array to rows. There are a number of reasons…
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Turning PostgreSQL rows into arrays
So far in this series, I have described how you can create arrays and retrieve information from them — both the actual data stored in the array, and information about the array, such as its length. But the coolest trick, or set of tricks, that I use in PostgreSQL is the ability to turn arrays…
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Looking in PostgreSQL arrays with ANY
So far, this series has looked at how to create PostgreSQL arrays, how to retrieve data from them, and how to get the length of an array’s outer and inner dimensions. But one of the most common actions that we’ll want to do with an array is look inside to see if a particular value…
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The real questions to ask offshore developers
Friends of mine, who are not software developers, have a small, retail Internet business. The original developers created the application in Python, and my friends are looking for a full-stack Web/Python developer to help them. Frustrated with their inability to find someone who can commit to their project, my friends have decided to hire offshore developers, which…
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PostgreSQL array indexes and length
In my last blog post, I introduced the idea of a PostgreSQL array, and showed how we can insert data into a table using either the curly-brace {} syntax, or the ARRAY construction syntax. In this post, I want to talk about PostgreSQL indexes and length — what happens when we retrieve from indexes that exist (and…
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Learning to love PostgreSQL arrays
I’ll admit it: When arrays were added to PostgreSQL a number of years ago, I thought that this was a really bad idea. I’m a firm believer in normalization when it comes to database design and storage; and the idea of putting multiple values inside of a single column struck me as particularly foolish. Besides,…
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Control-R, my favorite Unix shell command
If you use a modern, open-source Unix shell — and by that, I basically mean either bash or zsh — then you really should know this shortcut. Control-R is probably the shell command (or keystroke, to be technical about it) that I use most often, since it lets me search through my command history. Let’s…
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Starting a new software project? Don’t start coding right away.
It’s always fun to start a new project. I should know; I’ve been a consultant since 1995, and have started hundreds of projects of various shapes and sizes. It’s tempting, when I first meet a new client and come to an agreement, to dive right into the code, and start trying to solve their problems.…
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Summary of my “reduce” series
I teach Ruby and Python to a lot of people — in formal courses, and in one-on-one pairing sessions, both online and in person. I’ve found that for many people, the whole notion of functional programming seems strange and difficult, as well as something of a waste of time. After all, if you have objects,…