Creating migrations

Summary

This page generates a new Doctrine migration file and shows how to write its up and down methods.

Details

Migrations are used to create and/or edit the database structure. To generate a new migration file, use this command:

php vendor/bin/doctrine-migrations migrations:generate

It creates a PHP file like this one /data/doctrine/migrations/Version20220606131835.php that can then be edited in the IDE. You can add new queries in:

• public function up - these are executed when the migration is run.
• public function down - these are optional queries that undo the above changes.

Example

This example creates a new column named test. Add this in public function up:

$this->addSql('ALTER TABLE user ADD test VARCHAR(255) NOT NULL');

And its opposite in public function down:

$this->addSql('ALTER TABLE user DROP test');

FAQ

Q: Where are new migrations saved?

A: In data/doctrine/migrations, in the Frontend\Migrations namespace, as set in config/migrations.php.

Q: How do I undo the last migration?

A: Run php vendor/bin/doctrine-migrations migrate prev, which runs the down method of the latest executed migration.

Q: Can Doctrine write the migration for me?

A: Yes. After changing your entities, run php vendor/bin/doctrine-migrations diff, which generates a migration from the difference between the entity mapping and the database. Review the generated SQL before you run it.

Q: Is a failed migration rolled back?

A: config/migrations.php enables transactional and all_or_nothing. MySQL and MariaDB commit schema changes implicitly, so a failed ALTER TABLE may still leave earlier statements applied.