# Utility

## Querying across files with Apache Drill

Globbing, implicit columns, and the power of SQL

When I first used Apache Drill several years ago, it was one of those “holy crap this is amazing” moments. Moreover, every time since that I’ve thought “Oh, Drill could be really useful here” and spun it up, that thought has been quickly followed by “holy crap this is amazing” all over again. It’s just delightful. I keep thinking I should try out alternatives like Presto (which has two branches now) or Apache Impala, but I always start by spinning up Drill for comparison and never quite make it…

## match.arg

Lately I’ve been working with a lot of people whose first language is not R, which has given me more of an appreciation for R’s oddities. Some in retrospect were probably ill-advised, like partial matching with \$:

## Mapping leaves

Recursive functional programming

I love purrr.1 Aside from its anonymous function notation, one of the functions that made me love the package was at_depth, which iterates across a list at a specified level of nesting. It has since been deprecated in favor of modify_depth, which is more powerful, but is significantly more finicky.