Flask Databases with NeuralNine

Course Video

In this repository we will learn how to interact with Databses in Flask application. Here we will use SQLAlchemy as our Database.

what is modes.py file?

this is a file that is used to connect python classes to the database. we don't have database in python, so we have to create a class, then with it's help object relation mapping(ORM), we connect python class with the database such as SQlAlchemy or MySQL or PostgreSQL.

For example we have a Person class in python(model.py). It has its own attributes like Name, age, salary etc. So when we need to update those attributes in the database we will use models.py file to interact with DB and update our Db structure.

So, when we create a class in models.py we will import it into the app file, and then we create db instance in the app file, then we will import it into the models.py file.

we can create tables in the db and connect them with our app or we can create it in out models.py file.

only do onces, first time before running server

flask db init

Run both commands everytime - add any model class - add any field - change db - do any type of change

flask db migrate

flask db upgrade