The Help, the DBA Handbook, data to practise with, the videos and what is new, on one page.
If you came here from Calíope, this is the site seen from the app: what helps you use it, learn with it and try it. The Help and the DBA Handbook are the same text Calíope carries inside; the sample data, the test servers, the videos and the blog only live here.
What came in the latest version. The site describes the newest version of Calíope, so it can be ahead of the App Store.
The Help Calíope carries inside, section by section.
How each engine behaves —types, indexes, locks, configuration, backups, limits and errors—, with SQL examples. Choose an engine.
To try a tool without touching your own servers.
About 80 MB: two related tables, some 1,500 products with their real PNG photos, indexes, a foreign key and a view. The text is in Spanish, with accents and emoji, and some values are NULL on purpose. Open it from the SQLite Editor with Open…; it needs no connection.
Customers, products, 50,000 orders and their lines, with a view, an index, a sequence, an ENUM, two macros and a second schema. Open it in the DuckDB Editor, or select it in the Finder and press the space bar to see it with Quick Look.
The same test environment I develop Calíope against: one file, for a Mac with Docker, that brings up the engines you choose with their sample data. Before starting, it tells you how much memory your choice needs.
42 demo videos, 2 h 19 min in all. Each one has chapters, so you can jump to the part you need.
Articles on everyday database work. Each one gives a solution that does not need Calíope.
What took me years to learn to read in MySQL's EXPLAIN: why an index in possible_keys doesn't mean it gets used, what the Extra column warns you about and why a three-column index doesn't serve just any WHERE. With a table of 200,000 orders and the real plans.
The ways I filled tables to test an application, from the most naive to the one I use today: INSERTs by hand, the table that copies itself, a series generated with SQL and a procedure that reads the columns. With the code for each database engine and the version where it starts to work.
Every shortcut on the Mac and on the iPad with a keyboard, generated from the code.
Every function of every tool: what it does, on which engines and on which screens.
The database clients written for Calíope: what each one is written from and what it leaves out on purpose.
Read-only tools for an AI client on the same Mac. Off by default.
One app, SwiftUI end to end, the boundary with each engine and the sandbox.
What Calíope does with VoiceOver, Voice Control, larger text and the other accessibility features.
The same purchase covers Calíope on the Apple Watch and the Apple TV, which read what Calíope publishes to your own iCloud from your Mac, iPad, iPhone or Apple Vision Pro, and on Apple Vision Pro, where it is the whole app.
What has just shipped, what I am working on, what is planned and what I decided not to build, with the reason.
Frequently asked questions, troubleshooting and, for anything else, my email: on the Support page