### Type-Safe Queries with EntityManager

Source: https://mikro-orm.io

Perform fully type-safe queries using the EntityManager. This example shows how to find books by author name, populate related entities like 'author.profile', and order results by title. Changes to entities are tracked automatically, and `em.flush()` commits all changes in a single transaction.

```typescript
// fully type-safe queries
const books = await em.find(Book, {
  author: { name: 'Tolkien' },
}, {
  populate: ['author.profile'], // type-checked!
  orderBy: { title: 'asc' },
});

// all changes are tracked automatically
books[0].title = 'Updated Title';
em.remove(books[1]);

// single flush = one transaction, batched queries
await em.flush();

```

--------------------------------

### Define Entity with Mikro-ORM

Source: https://mikro-orm.io

Define a 'Book' entity with properties like id, title, author, and tags. This uses the `defineEntity` function and property helpers like `p.number()`, `p.string()`, `p.manyToOne()`, and `p.manyToMany()`. Infer the entity type using `InferEntity`.

```typescript
import { defineEntity, InferEntity, p } from '@mikro-orm/core';

export const Book = defineEntity({
  name: 'Book',
  properties: {
    id: p.number().primary(),
    title: p.string(),
    author: () => p.manyToOne(Author).ref(),
    tags: () => p.manyToMany(Tag),
  },
});

export type IBook = InferEntity<typeof Book>;

```

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