Database session management in FastAPI - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import the correct function for creating a database session.

FastAPI

from sqlalchemy.orm import [1]

Drag options to blanks, or click blank then click option'

ASessionLocal

Bsessionmaker

Ccreate_engine

DBase

Attempts:

3 left

💡 Hint

Common Mistakes

Using create_engine instead of sessionmaker

Importing Base instead of sessionmaker

Confusing SessionLocal with sessionmaker

The sessionmaker function is used to create a new session factory in SQLAlchemy, which is essential for managing database sessions in FastAPI.

2fill in blank

medium

Complete the code to create a new database session instance.

FastAPI

db = [1]()

Drag options to blanks, or click blank then click option'

Aengine

BBase

Csessionmaker

DSessionLocal

Attempts:

3 left

💡 Hint

Common Mistakes

Calling engine() instead of SessionLocal()

Using sessionmaker() directly without configuring it

Trying to use Base as a session

SessionLocal is the session factory created by sessionmaker. Calling it returns a new session instance.

3fill in blank

hard

Fix the error in the dependency function to properly close the database session.

FastAPI

def get_db():
    db = SessionLocal()
    try:
        yield [1]
    finally:
        db.close()

Drag options to blanks, or click blank then click option'

ASessionLocal

Bengine

Cdb

DBase

Attempts:

3 left

💡 Hint

Common Mistakes

Yielding the session factory instead of the session instance

Yielding the engine or Base instead of the session

Not yielding anything

The function should yield the session instance db so that the caller can use it. Yielding SessionLocal or other objects is incorrect.

4fill in blank

hard

Fill both blanks to create a session factory with autocommit disabled and autoflush enabled.

FastAPI

SessionLocal = sessionmaker(bind=engine, autocommit=[1], autoflush=[2])

Drag options to blanks, or click blank then click option'

AFalse

BTrue

CNone

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Setting autocommit to True causing unexpected commits

Disabling autoflush leading to stale queries

Using None or 0 instead of boolean values

By default, autocommit should be False to control transactions manually, and autoflush is often set to True to flush changes automatically before queries.

5fill in blank

hard

Fill all three blanks to define a FastAPI dependency that provides a database session and ensures it is closed after use.

FastAPI

def get_db():
    db = [1]()
    try:
        yield [2]
    finally:
        [3].close()

Drag options to blanks, or click blank then click option'

ASessionLocal

Bdb

Dengine

Attempts:

3 left

💡 Hint

Common Mistakes

Yielding the session factory instead of the session instance

Closing the wrong variable like engine instead of the session

Not closing the session at all

The dependency function creates a session by calling SessionLocal(), yields the session db for use, and finally closes the session with db.close().