PolySchemaWrite a migration once. Run it on any database.

Portable YAML or JSON schema migrations for PostgreSQL, MySQL, MariaDB and SQLite. Use the Go library or the command line.

Get Started

Install

GitHub

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Four engines, one file

Describe tables, columns, indexes, constraints and seed data in YAML or JSON. PolySchema writes the right SQL for PostgreSQL, MySQL, MariaDB and SQLite.

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Checked before it runs

Run -check to see what each engine can't do before a migration runs. Unsupported operations are refused before anything touches the database.

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Library or CLI

Embed your migrations in a Go binary with embed.FS and pass in your own *sql.DB, or run the standalone polyschema command from CI or a shell.

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Safe to run at startup

Each file runs in a transaction. An advisory lock on Postgres and MySQL stops app instances that start together from migrating twice.

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History and checksums

Each applied file is recorded with its SHA-256 checksum, so a file that was edited after it ran is caught instead of being silently ignored.

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Raw SQL when you need it

The sql operation takes a different statement for each engine, for anything the portable format doesn't cover.