Database migration in deployment in Flask - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a database migration in the context of Flask deployment?

A database migration is a way to update the database schema (structure) safely when the application changes, without losing existing data.

beginner

Which Flask extension is commonly used for database migrations?

Flask-Migrate is the common extension that helps manage database migrations using Alembic under the hood.

beginner

What command do you run to create a new migration script after changing your models?

You run flask db migrate -m "message" to generate a migration script reflecting model changes.

beginner

Why should you run flask db upgrade during deployment?

Running flask db upgrade applies the migration scripts to update the database schema to the latest version.

intermediate

What is the role of Alembic in Flask database migrations?

Alembic is the tool that Flask-Migrate uses to track and apply database schema changes safely.

Which Flask extension helps manage database migrations?

A Flask-Mail

B Flask-Login

C Flask-WTF

D Flask-Migrate

Flask-Migrate is designed to handle database migrations in Flask apps.

What command creates a new migration script after model changes?

A flask db migrate -m "message"

B flask db init

C flask run

D flask db upgrade

The 'flask db migrate' command generates migration scripts based on model changes.

What does flask db upgrade do?

A Creates a new migration script

B Applies migration scripts to update the database

C Runs the Flask app

D Initializes the migration environment

It applies the migration scripts to update the database schema.

Why are database migrations important during deployment?

A To update database schema without losing data

B To change the app's UI

C To restart the server

D To clear the database

Migrations update the database structure safely without data loss.

Which tool does Flask-Migrate use internally?

A SQLAlchemy

B Pip

C Alembic

D Jinja2

Alembic is the migration tool Flask-Migrate uses to track schema changes.

Explain the steps to perform a database migration in a Flask deployment.

Think about how you update the database schema safely after changing your code.

Why is it important to use migrations instead of manually changing the database during deployment?

Consider what could go wrong if you change the database by hand.