How do you define a TypeORM entity and register it in a NestJS feature module?

Q: How do you define a TypeORM entity and register it in a NestJS feature module?

@Entity('users') export class User { @PrimaryGeneratedColumn() id: number; @Column({ unique: true }) email: string; @Column({ select: false }) // excluded from SELECT by default password: string; @Column({ nullable: true }) name?: string; @CreateDateColumn() createdAt: Date; @UpdateDateColumn() updatedAt: Date; @OneToMany(() => Post, post => post.author) posts: Post[]; } // Feature module — register entity with forFeature() @Module({ imports: [TypeOrmModule.forFeature([User])], providers: [UsersService, UsersRepository], exports: [UsersService], }) export class UsersModule {} // Service — inject the TypeORM repository @Injectable() export class UsersService { constructor( @InjectRepository(User) private readonly userRepo: Repository , ) {} } TypeOrmModule.forFeature([User]) registers Repository in the module's DI scope. @InjectRepository(User) is the token used to inject the repository — matches forFeature() registration. select: false on @Column() excludes the field from SELECT queries unless explicitly selected. Entities must be referenced in TypeOrmModule.forRoot() entities array or glob — otherwise they are invisible. @OneToMany, @ManyToOne, @ManyToMany define relationships; always provide the inverse side.

Difficulty: 5/10

Entity definition, Module registration, Dependency injection

Decorate the class with @Entity() and annotate columns with @Column(), @PrimaryGeneratedColumn(), @CreateDateColumn(), etc. Register the entity in a feature module using TypeOrmModule.forFeature([Entity]) which makes Repository<Entity> available for injection via @InjectRepository().

Entity definition and feature module registration

Entity and module registration rules:

1
TypeOrmModule.forFeature([User]) registers Repository<User> in the module's DI scope.
2
@InjectRepository(User) is the token used to inject the repository — matches forFeature() registration.

How do you define a TypeORM entity and register it in a NestJS feature module?

Difficulty: 5/10

Entity definition, Module registration, Dependency injection

Decorate the class with @Entity() and annotate columns with @Column(), @PrimaryGeneratedColumn(), @CreateDateColumn(), etc. Register the entity in a feature module using TypeOrmModule.forFeature([Entity]) which makes Repository<Entity> available for injection via @InjectRepository().

Entity definition and feature module registration

Entity and module registration rules:

1
TypeOrmModule.forFeature([User]) registers Repository<User> in the module's DI scope.
2
@InjectRepository(User) is the token used to inject the repository — matches forFeature() registration.

How do you define a TypeORM entity and register it in a NestJS feature module?

Decorate the class with @Entity() and annotate columns with @Column(), @PrimaryGeneratedColumn(), @CreateDateColumn(), etc. Register the entity in a feature module using TypeOrmModule.forFeature([Entity]) which makes Repository<Entity> available for injection via @InjectRepository().

How do you define a TypeORM entity and register it in a NestJS feature module?

Decorate the class with @Entity() and annotate columns with @Column(), @PrimaryGeneratedColumn(), @CreateDateColumn(), etc. Register the entity in a feature module using TypeOrmModule.forFeature([Entity]) which makes Repository<Entity> available for injection via @InjectRepository().

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