Why migrations version your database schema in Supabase - See It in Action

Why migrations version your database schema

📖 Scenario: You are working on a Supabase project where your database schema changes over time as you add new features. You want to keep track of these changes safely and clearly.

🎯 Goal: Build a simple migration versioning setup that shows how to track changes to your database schema step-by-step.

📋 What You'll Learn

Create a migration version identifier

Add a description for the migration

Apply a schema change using SQL

Record the migration version in a tracking table

💡 Why This Matters

🌍 Real World

In real projects, migrations help teams safely update databases without losing data or causing errors.

💼 Career

Understanding migrations is key for backend developers and database administrators to manage evolving data structures.

1

Create a migration version variable

Create a variable called migration_version and set it to the string '001_initial_schema'.

Supabase

# Your code here

Hint

This variable helps identify the migration step.

2

Add a migration description

Create a variable called migration_description and set it to the string 'Create users table'.

Supabase

migration_version = '001_initial_schema'
# Your code here

Hint

This description explains what the migration does.

3

Write the SQL to create a users table

Create a variable called migration_sql and set it to the SQL string that creates a table named users with columns id (integer primary key) and email (text).

Supabase

migration_version = '001_initial_schema'
migration_description = 'Create users table'
# Your code here

Hint

Use triple quotes for multi-line SQL strings.

4

Record the migration in a migrations table

Write a SQL insert statement in a variable called record_migration_sql that inserts migration_version and migration_description into a table named migrations with columns version and description.

Supabase

migration_version = '001_initial_schema'
migration_description = 'Create users table'
migration_sql = '''CREATE TABLE users (id SERIAL PRIMARY KEY, email TEXT NOT NULL);'''
# Your code here

Hint

Use an f-string to insert variables into the SQL statement.