NestJS NestJS Database Integration & ORMs

Question 1

Which NestJS package provides first-class TypeORM integration?

Accepted Answer

@nestjs/typeorm

Answer

@nestjs/typeorm provides TypeOrmModule with forRoot() and forFeature() methods for integrating TypeORM into the NestJS DI system.

Question 2

What does `TypeOrmModule.forFeature([Entity])` do in a feature module?

Accepted Answer

Registers the entity's repository so it can be injected in that module

Answer

forFeature() registers the specified entities and makes their TypeORM repositories available for injection via @InjectRepository() within that module.

Question 3

How do you inject a TypeORM repository into a NestJS service?

Accepted Answer

@InjectRepository(User) private repo: Repository<User>

Answer

@InjectRepository(Entity) is the TypeORM-specific injection decorator that retrieves the entity's repository from the DI container.

Question 4

Which TypeORM method should be used to run database transactions in a NestJS service?

Accepted Answer

dataSource.transaction() or EntityManager in a transaction callback

Answer

dataSource.transaction() or injecting EntityManager inside a transaction callback ensures all operations use the same database transaction.

Question 5

What is the purpose of TypeORM migrations in a NestJS production application?

Accepted Answer

To safely evolve the database schema in a controlled, versioned manner

Answer

Migrations provide versioned, reversible SQL scripts that alter the database schema without losing data — essential in production where `synchronize: true` is dangerous.

NestJS Practice Test

NestJS Practice Test

NestJS NestJS Database Integration & ORMs