Presto is a fast SQL query engine, but it's different than most technologies in its class. Understanding the philosophy and architecture of Presto allows you to write more performant queries, and debug misbehaving ones. In these articles, you'll learn about Presto's approach to map-reduce, joins, data sources, and data flow. You'll understand why some join conditions are more efficient than others, why the small table should be on the right, when to use distributed joins, and how to structure your subqueries.

One of Python's strengths is its powerful generators. Even a basic understand of them unlocks the the ability to elegantly handle even huge datasets. But they hold some suprises in what is executed when -- understand them at a deeper level allows you to use and debug them more effectively.

Git's power is in collaboration, and that comes from remote branches. Everyone's used a remote branch, but juggling multiple remotes and keeping local and remote branches in sync can be challenging. Here, we explain how remote branches work, how to manage them effectively, and how to set one up yourself.

An important part of version control is the ability to go back to previous states -- particularly if your recent changes messed something up! Git has the powerful reset command, but it has a bewildering array of slightly-but-crucially-different modes. People generally start out memorizing a couple reset commands for common tasks, but still have questions like "what does git reset --soft do anyway?". In this article, we'll build up a mental model of how Git views changes, which will allow us to unlock the full power of reset.

Git is a powerful version control system, but the mental model can be complex. Beginners can find such concepts as fast-forward merges confusion, and sooner or later everyone ends up in the dreaded "detached head" mode. This article will build up a mental model of Git to understand what's really happening, ensuring that you're never trapped, and allowing you to perform impressive feats of Git surgery with aplomb.