@nestjs/typeorm

What is @nestjs/typeorm?

@nestjs/typeorm is an integration package for NestJS that provides seamless integration with TypeORM, a popular ORM (Object-Relational Mapper) for TypeScript and JavaScript. It allows developers to easily manage database connections, entities, repositories, and perform database operations in a structured and efficient manner.

What are @nestjs/typeorm's main functionalities?

Database Connection

This feature allows you to establish a connection to a database using TypeORM's `createConnection` method. You can specify the database type, host, port, username, password, and other connection options.

const connection = await createConnection({
  type: 'mysql',
  host: 'localhost',
  port: 3306,
  username: 'test',
  password: 'test',
  database: 'test',
  entities: [__dirname + '/**/*.entity{.ts,.js}'],
  synchronize: true,
});

Entity Definition

Entities in TypeORM are classes that map to database tables. This feature allows you to define entities using decorators like `@Entity`, `@Column`, and `@PrimaryGeneratedColumn`.

import { Entity, Column, PrimaryGeneratedColumn } from 'typeorm';

@Entity()
export class User {
  @PrimaryGeneratedColumn()
  id: number;

  @Column()
  name: string;

  @Column()
  age: number;
}

Repository Pattern

The repository pattern in TypeORM allows you to interact with the database using repositories. This feature demonstrates how to use the `@InjectRepository` decorator to inject a repository and perform CRUD operations.

import { Injectable } from '@nestjs/common';
import { InjectRepository } from '@nestjs/typeorm';
import { Repository } from 'typeorm';
import { User } from './user.entity';

@Injectable()
export class UserService {
  constructor(
    @InjectRepository(User)
    private userRepository: Repository<User>,
  ) {}

  findAll(): Promise<User[]> {
    return this.userRepository.find();
  }

  findOne(id: string): Promise<User> {
    return this.userRepository.findOne(id);
  }

  async remove(id: string): Promise<void> {
    await this.userRepository.delete(id);
  }
}

Other packages similar to @nestjs/typeorm

sequelize

Sequelize is a promise-based Node.js ORM for Postgres, MySQL, MariaDB, SQLite, and Microsoft SQL Server. It features solid transaction support, relations, eager and lazy loading, read replication, and more. Compared to @nestjs/typeorm, Sequelize offers a different API and supports a wider range of SQL dialects.

mongoose

Mongoose is an ODM (Object Data Modeling) library for MongoDB and Node.js. It provides a straightforward, schema-based solution to model your application data. While @nestjs/typeorm is designed for SQL databases, Mongoose is specifically for MongoDB, making it a better choice for NoSQL databases.

prisma

Prisma is a next-generation ORM that can be used to build GraphQL servers, REST APIs, microservices, and more. It provides a type-safe database client and a powerful migration system. Prisma's approach to database management is more modern compared to TypeORM, offering better type safety and developer experience.

README

A progressive Node.js framework for building efficient and scalable server-side applications.

Description

TypeORM module for Nest.

Installation

$ npm i --save @nestjs/typeorm typeorm@0.2

Quick Start

Overview & Tutorial

Support

Nest is an MIT-licensed open source project. It can grow thanks to the sponsors and support by the amazing backers. If you'd like to join them, please read more here.

Stay in touch

• Author - Kamil Myśliwiec
• Website - https://nestjs.com
• Twitter - @nestframework

License

Nest is MIT licensed.