Schema definition in NestJS - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a schema in NestJS?

A schema in NestJS defines the structure of data for a database model. It tells NestJS what fields to expect and their types, like a blueprint for data.

beginner

How do you create a schema using Mongoose in NestJS?

You create a schema by defining a class with decorators like @Schema() and @Prop() to specify fields. Then use SchemaFactory.createForClass() to generate the schema.

beginner

What is the role of @Prop() decorator in NestJS schema definition?

@Prop() marks a class property as a schema field and lets you set options like type, required, or default value for that field.

intermediate

Why use SchemaFactory.createForClass() in NestJS?

SchemaFactory.createForClass() converts your decorated class into a Mongoose schema that NestJS can use to interact with the database.

intermediate

How does schema definition help with data validation in NestJS?

Schema definition sets rules for data types and required fields, so NestJS can check data before saving it, preventing errors and keeping data clean.

Which decorator is used to define a schema class in NestJS with Mongoose?

A @Entity()

B @Model()

C @Schema()

D @Document()

@Schema() marks a class as a schema definition for Mongoose in NestJS.

What does the @Prop() decorator do in a NestJS schema?

A Defines a schema field with options

B Creates a database connection

C Runs a query

D Imports a module

@Prop() defines a property as a schema field and allows setting its options.

How do you generate a Mongoose schema from a class in NestJS?

A SchemaFactory.createForClass()

B new Schema()

C createSchema()

D Schema.create()

SchemaFactory.createForClass() converts a decorated class into a Mongoose schema.

Why is schema definition important in NestJS?

A It styles the UI

B It defines data structure and validation rules

C It manages user sessions

D It handles HTTP requests

Schema defines how data looks and validates it before saving.

Which of these is NOT a typical option you can set in @Prop()?

A required

B default

C type

D route

'route' is not an option for @Prop(); it's unrelated to schema fields.

Explain how to define a schema in NestJS using Mongoose decorators.

Think about how classes and decorators work together to build schemas.

Describe why schema definitions are useful in NestJS applications.

Consider how data safety and structure matter in apps.