PRJ2: Database Guide

Your Database

You will run your own database on your own computer while developing. But your deployed app will have its own database.

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How init.sql Works

Every time you push code, your database:

1. Gets deleted (clean slate)
2. Gets recreated
3. Runs your db/init.sql

Your db/init.sql should create all tables and test data:

CREATE TABLE customers (
    id SERIAL PRIMARY KEY,
    name VARCHAR(100) NOT NULL,
    email VARCHAR(255)
);

CREATE TABLE orders (
    id SERIAL PRIMARY KEY,
    customer_id INTEGER REFERENCES customers(id),
    total DECIMAL(10,2)
);

INSERT INTO customers (name, email) VALUES ('Test User', 'test@example.com');

Tip

Test your SQL locally before pushing. Syntax errors will break deployment.

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Using pgAdmin

pgAdmin lets you browse your deployed database in a web browser — useful for checking tables, viewing data, and debugging.

See the pgAdmin Setup guide for login and connection instructions.

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FAQ

Why did my data disappear? Database resets on every deploy. This is intentional—your db/init.sql is always the source of truth.

Can I keep data between deploys? In a real life situation, it would be disastrous if production data gets lost every a deployment. Instead of resetting the database, developers do 'migrations'. However, this is not in scope of PRJ2.

My init.sql has an error? Check pgAdmin or fix your SQL and push again.