SQLite

ATTACH Database

Query across multiple database files in one connection.

#attach#multi-db#migration

Code

sqlite

-- Attach another database file
ATTACH DATABASE 'archive.db' AS archive;

-- List attached databases
PRAGMA database_list;

-- Query across databases
SELECT * FROM main.users
UNION ALL
SELECT * FROM archive.users WHERE archived_at < '2024-01-01';

-- Copy data between databases
INSERT INTO archive.users
SELECT * FROM main.users WHERE last_login < '2023-01-01';
DELETE FROM main.users WHERE last_login < '2023-01-01';

-- Detach when done
DETACH DATABASE archive;

All snippets