Rolling back migrations in Supabase - Mini Project: Build & Apply

Rolling Back Migrations in Supabase

📖 Scenario: You are managing a Supabase project where you have applied database schema changes using migrations. Sometimes, you need to undo a migration to fix mistakes or revert to a previous state.Imagine you deployed a migration that added a new table, but you realized it was incorrect. You want to roll back that migration safely.

🎯 Goal: Learn how to roll back the last applied migration in Supabase using the CLI commands and understand the migration files involved.

📋 What You'll Learn

Create a migration file with a specific name

Add a configuration variable for the migration directory

Use the Supabase CLI command to roll back the last migration

Verify the rollback command is correctly configured

💡 Why This Matters

🌍 Real World

Rolling back migrations is common when a database change causes errors or needs adjustment. It helps maintain data integrity and application stability.

💼 Career

Database migration management is a key skill for backend developers, DevOps engineers, and cloud architects working with modern cloud databases like Supabase.

1

Create a migration file named 001_create_users_table.sql

Create a migration file called 001_create_users_table.sql with the following SQL content exactly: CREATE TABLE users (id SERIAL PRIMARY KEY, name TEXT NOT NULL);

Supabase

# Create the migration file named 001_create_users_table.sql with the specified SQL content
# Your code here

Hint

Migration files in Supabase are SQL files named with a number prefix and description.

2

Add a configuration variable MIGRATION_DIR set to ./supabase/migrations

Add a variable called MIGRATION_DIR and set it to the string "./supabase/migrations" to specify where migration files are stored.

Supabase

001_create_users_table.sql:
CREATE TABLE users (id SERIAL PRIMARY KEY, name TEXT NOT NULL);

MIGRATION_DIR = "./supabase/migrations"
# Your code here

Hint

This variable helps you refer to the migrations folder easily in commands.

3

Use the Supabase CLI command to roll back the last migration

Write the Supabase CLI command to roll back the last migration using the supabase db reset --project-ref command. Use the exact command: supabase db reset --project-ref your-project-ref --force

Supabase

001_create_users_table.sql:
CREATE TABLE users (id SERIAL PRIMARY KEY, name TEXT NOT NULL);

MIGRATION_DIR = "./supabase/migrations"

# Write the rollback command below
# Your code here

Hint

The db reset command rolls back all migrations and reapplies them. The --force flag skips confirmation.

4

Verify the rollback command includes the correct project reference

Ensure the rollback command includes the project reference your-project-ref as shown: supabase db reset --project-ref your-project-ref --force

Supabase

001_create_users_table.sql:
CREATE TABLE users (id SERIAL PRIMARY KEY, name TEXT NOT NULL);

MIGRATION_DIR = "./supabase/migrations"

supabase db reset --project-ref your-project-ref --force

# Verify the command correctness
# Your code here

Hint

Double-check the command to avoid mistakes when rolling back migrations.