Simon Willison’s Weblog

geojson-to-sqlite (via) I just put out the first release of geojson-to-sqlite—a CLI tool that can convert GeoJSON files (consisting of a Feature or a set of features in a FeatureCollection) into a table in a SQLite database. If you use the --spatialite option it will initalize the table with SpatiaLite and store the geometries in a spacially indexed geometry field—without that option it stores them as GeoJSON.

# 31st January 2020, 6:40 am / geojson, sqlite, spatialite, projects, gis, cli

Generated Columns in SQLite (via) SQLite 3.31.0 released today, and generated columns are the single most notable new feature. PostgreSQL 12 added these in October 2019, and MySQL has had them since 5.7 in October 2015. MySQL and SQLite both offer either “stored” or “virtual” generated columns, with virtual columns being calculated at runtime. PostgreSQL currently only supports stored columns.

# 24th January 2020, 4:20 am / mysql, sql, postgresql, sqlite

Serving 100µs reads with 100% availability (via) Fascinating use-case for SQLite from Segment: they needed a massively replicated configuration database across all of their instances that process streaming data. They chose to make the configuration available as a ~50GB SQLite database file mirrored to every instance, meaning lookups against that data could complete in microseconds. Changes to the central MySQL configuration store are pulled every 2-3 seconds, resulting in a trade-off of consistency for availability which fits their use-case just fine.

# 10th January 2020, 5:15 am / scaling, sqlite, segment

athena-sqlite (via) Amazon Athena is the AWS tool for querying data stored in S3—as CSV, JSON or Apache Parquet files—using SQL. It’s an interesting way of buliding a very cheap data warehouse on top of S3 without having to run any additional services. Athena recently added a query federation SDK which lets you define additional custom data sources using Lambda functions. Damon Cortesi used this to write a custom connector for SQLite, which lets you run queries against data stored in SQLite files that you have uploaded to S3. You can then run joins between that data and other Athena sources.

# 18th December 2019, 9:05 am / sqlite, sql, aws, athena, s3, parquet

sqlite-transform. I released a new CLI tool today: sqlite-transform, which lets you run “transformations” against a SQLite database. I built it out of frustration of constantly running into CSV files that use horrible American date formatting—the “sqlite-transform parsedatetime my.db mytable col1” command runs dateutil’s parser against those columns and replaces them with a nice, sortable ISO formatted timestamp. I’ve also added a “sqlite-transform lambda” command that lets you specify Python code directly on the command-line that should be used to transform every value in a specified column.

# 4th November 2019, 2:41 am / projects, sqlite, cli

goodreads-to-sqlite (via) This is so cool! Tobias Kunze built a Python CLI tool to import your Goodreads data into a SQLite database, inspired by github-to-sqlite and my various other Dogsheep tools. It’s the first Dogsheep style tool I’ve seen that wasn’t built by me—and Tobias’ write-up includes some neat examples of queries you can run against your Goodreads data. I’ve now started using Goodreads and I’m importing my books into my own private Dogsheep Datasette instance.

# 14th October 2019, 4:07 am / dogsheep, books, datasette, sqlite, cli

SQL Murder Mystery in Datasette (via) “A crime has taken place and the detective needs your help. The detective gave you the  crime scene report, but you somehow lost it. You vaguely remember that the crime  was a murder that occurred sometime on ​Jan.15, 2018 and that it took place in SQL  City. Start by retrieving the corresponding crime scene report from the police  department’s database.”—Really fun game to help exercise your skills with SQL by the NU Knight Lab. I loaded their SQLite database into Datasette so you can play in your browser.

# 7th October 2019, 11:37 pm / datasette, projects, sql, sqlite

genome-to-sqlite. I just found out 23andMe let you export your genome as a zipped TSV file, so I wrote a little Python command-line tool to import it into a SQLite database.

# 19th September 2019, 3:58 pm / projects, datasette, genetics, sqlite

sqlite-utils 1.11. Amjith Ramanujam contributed an excellent new feature to sqlite-utils, which I’ve now released as part of version 1.11. Previously you could enable SQLite full-text-search on a table using the .enable_fts() method (or the “sqlite-utils enable-fts” CLI command) but it wouldn’t reflect future changes to the table—you had to use populate_fts() any time you inserted new records. Thanks to Amjith you can now pass create_triggers=True (or --create-triggers) to cause sqlite-utils to automatically add triggers that keeps the FTS index up-to-date any time a row is inserted, updated or deleted from the table.

# 3rd September 2019, 1:05 am / projects, sqlite, full-text-search, sqlite-utils, cli

Working with many-to-many relationships in sqlite-utils (via) I just released sqlite-utils 1.9 with syntactic sugar support for creating many-to-many relationships for records stored in SQLite databases.

# 4th August 2019, 3:57 am / projects, sqlite, sqlite-utils

healthkit-to-sqlite. Ever since I got an Apple Watch I’ve been itching to get my hands on the step tracking and health data that it’s been collecting for me. I know it’s there in a SQLite database on my wrist, but I couldn’t figure out how to get it! A few days ago I stumbled across the “Export Health Data” button in the iOS Health app, and it turns out it creates a zip file containing XML with a full dump of the data collected by Apple Health. healthkit-to-sqlite is the tool I’ve built that can read that export and use it to create a SQLite database ready to be queried and explored with Datasette. It’s a pretty basic implementation but it’s already giving me access to over 3 million rows of data. Lots of potential here for interesting work with personal analytics.

# 22nd July 2019, 3:34 am / dogsheep, health, datasette, sqlite