Database migrations with Flask-Migrate - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of Flask-Migrate in a Flask application?

Flask-Migrate helps manage database schema changes over time by creating and applying migrations, so you can update your database structure without losing data.

beginner

Which command initializes Flask-Migrate in your Flask project?

The command flask db init sets up the migration environment by creating a migrations folder to track changes.

beginner

What does the command flask db migrate -m "message" do?

It creates a new migration script that records changes in your database models, with a message describing the update.

beginner

How do you apply the migration scripts to update the database schema?

Use flask db upgrade to apply the latest migration scripts and update the database structure accordingly.

intermediate

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

Migrations keep track of changes safely, allow easy rollback, and help multiple developers stay in sync without losing data or causing errors.

Which Flask-Migrate command creates the migration folder?

A flask db init

B flask db migrate

C flask db upgrade

D flask db create

The flask db init command initializes the migration environment by creating the migrations folder.

What does flask db upgrade do?

A Deletes old migration files

B Creates a new migration script

C Applies migration scripts to update the database

D Rolls back the last migration

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

When should you run flask db migrate?

A After changing your database models

B Before initializing migrations

C To apply migrations to the database

D To delete migration history

You run flask db migrate after changing your models to create a migration script reflecting those changes.

Which file or folder does Flask-Migrate create to track migrations?

A models.py file

B migrate.py file

C db.sqlite file

D migrations folder

Flask-Migrate creates a migrations folder to store migration scripts and track changes.

What is a key benefit of using Flask-Migrate in a team project?

A It automatically writes your models

B It helps keep database schema changes synchronized safely

C It replaces the need for a database

D It speeds up the Flask server

Flask-Migrate helps teams keep database schema changes synchronized and safe across different environments.

Explain the typical workflow for managing database changes using Flask-Migrate.

Think about the commands you run step-by-step after changing your models.

Why is it better to use Flask-Migrate instead of manually editing the database schema?

Consider safety and teamwork benefits.