Migrate from another tool

Nothing here asks you to rewrite applied history. Each page starts from a directory the other tool wrote, converts it, and shows the state afterwards. Every command on every page runs in this repository’s continuous integration against the version of Ptah the page was published with.

Pick the tool you are coming from

golang-migrateConvert NNN_name.up.sql and .down.sql pairs, including a migration whose down file was never written.

GooseConvert annotated single files, including a statement block and a migration that must run outside a transaction.

dbmateConvert timestamped single files, and read what the conversion did to their version numbers.

FlywayConvert versioned, undo and repeatable scripts, and learn what a repeatable becomes.

LiquibaseConvert the changesets that carry SQL, and read the refusal that names the ones that do not.

AtlasKeep the atlas.hcl, the directory and the commands, and run them through ptah-compat.

More tools are being added here one at a time. Until a tool has its own page, Import an existing migration directory covers the conversion and carries the format table for every source Ptah reads.

Two different moves

Converting a directory and keeping your commands are separate decisions, and you do not have to make both.

Convert the directory. ptah migrations import reads the other tool’s layout and writes Ptah’s, sealed with ptah.sum. The source directory is left untouched. This is what the pages above walk through.

Keep the commands. If you run Atlas today, ptah-compat reads the atlas.hcl you have and answers the commands you already run, with no conversion at all. Run an Atlas project on ptah-compat is the first mile, command by command; Migrate from Atlas carries on from there for readers who want to go native.

What a conversion does not do

A converted directory is a set of files. It says nothing about the databases that already ran the old tool, and applying it to one of them would replay migrations those databases already have.

Record that history as applied first. Adopt an existing database is the procedure, and it is the step people skip.