What is the form of my local postgresql database url?

I am going through a flask/sqlalchemy tutorial https://pythonhosted.org/Flask-SQLAlchemy/quickstart.html#a-minimal-application and I configured my database url to be: postgres://username:password@localhost:5432/dbname when I run db.create_all() in the interactive python shell it doesn't throw any errors, but it doesn't do anything either. From what I understand it is supposed to create the User table with three columns; id, username, and email . ``` from flask import Flask, url_for, render_template from flask.ext.sqlalchemy import SQLAlchemy app = Flask(__name__) app.config['SQLALCHEMY_DATABASE_URI'] = 'postgres://username:password@localhost:5432/dbname' db = SQLAlchemy(app) class User(db.Model): id = db.Column(db.Integer, primary_key=True) username = db.Column(db.String(80), unique=True) email = db.Column(db.String(120), unique=True) def __init__(self, username, email): self.username = username self.email = email def __repr__(self): return '<User %r>' % self.username app.debug = True @app.route("/") def hello(): return render_template('hello.html') if __name__ == "__main__": app.run() ```