Many of beets’ commands are built around query strings: searches that select tracks and albums from your library. This page explains the query string syntax, which is meant to vaguely resemble the syntax used by Web search engines.
$ beet list love
will show all tracks matching the query string love. Any unadorned word like this matches anywhere in a track’s metadata, so you’ll see all the tracks with “love” in their title, in their album name, in the artist, and so on.
For example, this is what I might see when I run the command above:
Against Me! - Reinventing Axl Rose - I Still Love You Julie Air - Love 2 - Do the Joy Bag Raiders - Turbo Love - Shooting Stars Bat for Lashes - Two Suns - Good Love ...
Multiple keywords are implicitly joined with a Boolean “and.” That is, if a query has two keywords, it only matches tracks that contain both keywords. For example, this command:
$ beet ls magnetic tomorrow
matches songs from the album “The House of Tomorrow” by The Magnetic Fields in my library. It doesn’t match other songs by the Magnetic Fields, nor does it match “Tomorrowland” by Walter Meego—those songs only have one of the two keywords I specified.
Sometimes, a broad keyword match isn’t enough. Beets supports a syntax that lets you query a specific field—only the artist, only the track title, and so on. Just say field:value, where field is the name of the thing you’re trying to match (such as artist, album, or title) and value is the keyword you’re searching for.
For example, while this query:
$ beet list dream
matches a lot of songs in my library, this more-specific query:
$ beet list artist:dream
only matches songs by the artist The-Dream. One query I especially appreciate is one that matches albums by year:
$ beet list -a year:2012
Recall that -a makes the list command show albums instead of individual tracks, so this command shows me all the releases I have from this year.
You can query for strings with spaces in them by quoting or escaping them using your shell’s argument syntax. For example, this command:
$ beet list the rebel
shows several tracks in my library, but these (equivalent) commands:
$ beet list "the rebel" $ beet list the\ rebel
only match the track “The Rebel” by Buck 65. Note that the quotes and backslashes are not part of beets’ syntax; I’m just using the escaping functionality of my shell (bash or zsh, for instance) to pass the rebel as a single argument instead of two.
While ordinary keywords perform simple substring matches, beets also supports regular expression matching for more advanced queries. To run a regex query, use an additional : between the field name and the expression:
$ beet list 'artist::Ann(a|ie)'
That query finds songs by Anna Calvi and Annie but not Annuals. Similarly, this query prints the path to any file in my library that’s missing a track title:
$ beet list -p title::^$
To search all fields using a regular expression, just prefix the expression with a single :, like so:
$ beet list :Ho[pm]eless
Regular expressions are case-sensitive and build on Python’s built-in implementation. See Python’s documentation for specifics on regex syntax.
For numeric fields, such as year, bitrate, and track, you can query using one- or two-sided intervals. That is, you can find music that falls within a range of values. To use ranges, write a query that has two dots (..) at the beginning, middle, or end of a string of numbers. Dots in the beginning let you specify a maximum (e.g., ..7); dots at the end mean a minimum (4..); dots in the middle mean a range (4..7).
For example, this command finds all your albums that were released in the ‘90s:
$ beet list -a year:1990..1999
and this command finds MP3 files with bitrates of 128k or lower:
$ beet list format:MP3 bitrate:..128000
Sometimes it’s useful to find all the items in your library that are (recursively) inside a certain directory. Use the path: field to do this:
$ beet list path:/my/music/directory
In fact, beets automatically recognizes any query term containing a path separator (/ on POSIX systems) as a path query, so this command is equivalent:
$ beet list /my/music/directory
Note that this only matches items that are already in your library, so a path query won’t necessarily find all the audio files in a directory—just the ones you’ve already added to your beets library.