Model definition in Flask - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import SQLAlchemy from flask_sqlalchemy.

Flask

from flask_sqlalchemy import [1]

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

AModel

BFlask

CSQLAlchemy

DBase

Attempts:

3 left

💡 Hint

Common Mistakes

Importing 'Model' directly instead of 'SQLAlchemy'.

Using 'Flask' which is unrelated to models.

Trying to import 'Base' which is not from flask_sqlalchemy.

The SQLAlchemy class is imported from flask_sqlalchemy to create the database object.

2fill in blank

medium

Complete the code to define a model class named User inheriting from the base model.

Flask

class User([1]):

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

Adb.Model

BBase

CModel

Dobject

Attempts:

3 left

💡 Hint

Common Mistakes

Inheriting from 'object' which is a plain Python class.

Using 'Base' which is from SQLAlchemy core, not Flask-SQLAlchemy.

Using 'Model' without prefix which causes NameError.

In Flask-SQLAlchemy, models inherit from db.Model to gain database features.

3fill in blank

hard

Fix the error in the model field definition to create an integer primary key named id.

Flask

id = db.Column([1], primary_key=True)

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Adb.Integer

Bdb.Float

Cdb.Boolean

Ddb.String(50)

Attempts:

3 left

💡 Hint

Common Mistakes

Using String type for primary key which is uncommon here.

Using Boolean or Float which are not suitable for primary keys.

The id field should be a db.Integer type to serve as a primary key.

4fill in blank

hard

Fill both blanks to define a username column that is a string of max length 80 and must be unique.

Flask

username = db.Column([1](80), [2]=True)

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Adb.String

Bunique

Cnullable

Ddb.Integer

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'nullable' instead of 'unique' for uniqueness.

Using 'Integer' instead of 'String' for username.

The username column uses db.String(80) for length and unique=True to ensure no duplicates.

5fill in blank

hard

Fill all three blanks to define an email column that is a string of max length 120, unique, and cannot be null.

Flask

email = db.Column([1](120), [2]=True, [3]=False)

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

Adb.Integer

Bunique

Cnullable

Ddb.String

Attempts:

3 left

💡 Hint

Common Mistakes

Setting nullable=True which allows empty emails.

Using Integer type for email which is incorrect.

The email column uses db.String(120) for length, unique=True to avoid duplicates, and nullable=False to require a value.