Databases

Web applications need to store data.

Instead of keeping the data in program memory (where it would get lost when the application restarts) or saving it to a file, web applications typically store information in databases.

In this week, we'll focus on relational databases. In the begining of the week, we will only learn about SQL alone, then we will learn how to use SQL and Flask all together.

While there are some use cases for other styles of database, relational databases are more generally applicable, and illustrate many of the principles you'd need to know to use a non-relational database.

To start, we'll focus on selecting data from tables in SQLite, a database that is both powerful and simple to use. Later on, you'll learn how to create, update, and delete data, as well as how to manage the structure of the data that's stored in the database.