B4nan

@Entity()
export class Author {

  // only `name` will be considered as required for `em.create()`
  [OptionalProps]?: 'createdAt' | 'updatedAt';

  @PrimaryKey()
  id!: number;

  @Property({ defaultRaw: 'current_timestamp()' })

B4nan

const god = em.create(Author, {
  name: 'God', // validates required properties
  email: 'god@heaven.io',
  books: [{
    title: 'Bible, part 1',
    tags: [{ name: 'old' }, { name: 'bestseller' }],
  }],
}, { persist: true }); // we can enable this globally via `persistOnCreate: true`
await em.flush();

B4nan

const book = {} as Book;
const dto = wrap(book).toObject(); // EntityDTO<Book>

// this is now possible, but with the PK union type, we would need to type cast all the time
const name = dto.author.name;

B4nan

import { expr } from '@mikro-orm/core';

const res1 = await em.find(Book, {
  // the type argument is optional, use it to get autocomplete on the entity properties
  [expr<Book>(['price', 'createdAt'])]: { $lte: [100, new Date()] },
});

// will issue query similar to this:
// select `b0`.* from `book` as `b0` where (`b0`.`price`, `b0`.`created_at`) <= (?, ?)

B4nan

const book = await em.findOneOrFail(Book, 1, { populate: ['author'] });

// update existing book's author's name
wrap(book).assign({
  author: {
    name: 'New name...',
  },
}, { updateByPrimaryKey: false });

B4nan

const book = await em.findOneOrFail(Book, 1, { populate: ['author'] });

// update existing book's author's name
wrap(book).assign({
  author: {
    id: book.author.id,
    name: 'New name...',
  },
});

B4nan

const res1 = await em.createQueryBuilder(Publisher).insert({
  name: 'p1',
  type: PublisherType.GLOBAL,
});
// res1 is of type `QueryResult<Publisher>`
console.log(res1.insertId);

const res2 = await em.createQueryBuilder(Publisher)
  .select('*')
  .where({ name: 'p1' })

B4nan

@Entity()
export class Book {

  @ManyToOne(() => Author, { wrappedReference: true })
  author!: IdentifiedReference<Author>;

  constructor(authorId: number) {
    this.author = Reference.createFromPK(Author, authorId);
  }

B4nan

import { MikroORM, Utils } from '@mikro-orm/core';

await MikroORM.init({
  migrations: {
    path: 'dist/migrations',
    pathTs: 'src/migrations',
  },
  // or alternatively
  // migrations: {
  //   path: Utils.detectTsNode() ? 'src/migrations' : 'dist/migrations',

B4nan

// first partially load author entities
const r1 = await em.find(Author, {}, { fields: ['id'] });
r1[0].email = 'lol'; // let's change one of the emails
console.log(r1[0].name); // undefined, not loaded

// reload full entities - no `refresh: true` needed!
const r2 = await em.find(Author, {});
console.log(r2[0]); // fully loaded author entity, but `email` is changed to 'lol'
console.log(r1[0] === r2[0]); // true, same entity instance, just updated!