Connection pooling in FastAPI - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is connection pooling in FastAPI?

Connection pooling is a technique to reuse database connections instead of opening a new one for each request. It improves performance by keeping a pool of open connections ready to use.

beginner

Why is connection pooling important in web applications?

It reduces the time and resources needed to connect to the database repeatedly. This makes the app faster and handles more users smoothly.

intermediate

How do you typically implement connection pooling in FastAPI?

You use a database library like SQLAlchemy or asyncpg that supports pooling. You create a pool object and share it across requests to get connections from it.

beginner

What happens if you don't use connection pooling in FastAPI?

Each request opens and closes a new database connection, which slows down the app and can overload the database server.

beginner

Name one popular library used with FastAPI for connection pooling.

SQLAlchemy is a popular library that supports connection pooling and works well with FastAPI.

What does connection pooling do in FastAPI?

A Closes all database connections after each request

B Reuses database connections to improve performance

C Creates a new database connection for every request

D Prevents database connections from opening

Connection pooling keeps a set of open connections ready to reuse, speeding up database access.

Which library is commonly used with FastAPI for connection pooling?

A SQLAlchemy

B Django

C Flask

D React

SQLAlchemy supports connection pooling and integrates well with FastAPI.

What is a risk of not using connection pooling?

A Faster database queries

B Automatic caching of data

C More memory available

D Database overload and slow app response

Opening and closing connections for every request can overload the database and slow down the app.

In FastAPI, connection pools are usually created by:

A Using a database library that supports pooling

B Writing raw SQL queries

C Manually opening connections in each route

D Disabling database connections

Libraries like SQLAlchemy or asyncpg handle connection pooling automatically.

Connection pooling helps FastAPI apps to:

A Avoid using databases

B Use more CPU for each request

C Handle more users efficiently

D Increase network latency

By reusing connections, apps can serve more users without delays.

Explain connection pooling and why it matters in FastAPI applications.

Think about how opening a door once and keeping it open saves time compared to opening it every time.

Describe how you would set up connection pooling in a FastAPI project.

Consider how a shared pool is like a parking lot with ready spaces for cars.