How to Create Migrations
In this document, you’ll learn how to create a Migration using Typeorm on your Medusa backend.
Create Migration File
To create a migration that makes changes to your Medusa schema, run the following command:
npx typeorm migration:create -n UserChanged --dir src/migrations
This will create the migration file in the path you specify. You can use this without the need to install Typeorm's CLI tool. You can then go ahead and make changes to it as necessary.
The migration file must be inside the src/migrations
directory. When you run the build command, it will be transpiled into the directory dist/migrations
. The migrations run
command can only pick up migrations under the dist/migrations
directory on a Medusa backend. This applies to migrations created in a Medusa backend, and not in a Medusa plugin. For plugins, check out the Plugin's Structure section.
You can alternatively use Typeorm's generate
command to generate a Migration file from existing database tables, which requires setting up a data source in Typeorm. Check out Typeorm's documentation to learn how to create a data source, then use the generate command.
Write Migration File
The migration file contains the necessary commands to create the database columns, foreign keys, and more.
You can learn more about writing the migration file in You can learn more about writing migrations in Typeorm’s Documentation.
Build Files
Before you can run the migrations you need to run the build command to transpile the TypeScript files to JavaScript files:
- npm
- Yarn
npm run build
yarn run build
Run Migration
The last step is to run the migration with the command detailed earlier
medusa migrations run
If you check your database now you should see that the change defined by the migration has been applied successfully.