What are SQLAlchemy migrations and how do I use them?

What are SQLAlchemy migrations and how do I use them?

SQLAlchemy migrations are a way to manage changes to your database schema over time. They allow you to create, modify, and delete tables and columns in a structured manner. You can use a tool like Alembic, which is designed to work with SQLAlchemy, to handle these migrations.

How do I set up Alembic for my project?

To set up Alembic, first install it using pip: pip install alembic. Then, run alembic init <directory> to create a new migration environment. This will generate a directory with configuration files and a versions folder for your migration scripts.

Can you show me an example of creating a migration?

Sure! After setting up Alembic, you can create a migration script by running alembic revision -m "create users table". This will create a new script in the versions folder where you can define the changes to your schema.

How do I apply the migration to the database?

To apply the migration, use the command alembic upgrade head. This will apply all pending migrations to your database, updating the schema accordingly.