Что такое документ BSON?

// A minimal MongoDB document
{
  _id: ObjectId('64a2f3b1c9e7e12345678901'),
  name: 'Alice',
  age: 30,
  active: true
}
// _id is auto-generated if omitted on insert
// ObjectId encodes the insert timestamp in its first 4 bytes

// Explicit BSON number types in mongosh
db.products.insertOne({
  name: 'Widget',
  quantity: NumberInt(100),       // 32-bit integer
  price: NumberDecimal('9.99'),   // Exact decimal for money
  weight: 0.45                    // Double (64-bit float)
});

// Always use BSON Date, not strings
db.events.insertOne({
  title: 'Conference',
  startDate: new Date('2024-09-01'),   // BSON Date
  endDate: ISODate('2024-09-03T18:00:00Z')
});

// Range query works perfectly on Date fields:
db.events.find({ startDate: { $gte: new Date('2024-01-01') } });

// Nested sub-document example
{
  _id: ObjectId('...'),
  name: 'Bob',
  address: {
    street: '123 Main St',
    city: 'Chicago',
    state: 'IL',
    zip: '60601'
  },
  employer: {
    name: 'Acme Corp',
    since: ISODate('2020-03-01')
  }
}

// Query by nested field:
db.users.find({ 'address.city': 'Chicago' });

// Document with arrays of primitives and sub-documents
{
  _id: ObjectId('...'),
  productName: 'Smart TV',
  tags: ['electronics', '4K', 'HDR'],
  reviews: [
    { user: 'alice', rating: 5, comment: 'Love it!' },
    { user: 'bob',   rating: 4, comment: 'Good value.' }
  ]
}

// Query: documents where tags array contains '4K'
db.products.find({ tags: '4K' });

// Extracting timestamp from ObjectId in mongosh
const id = ObjectId('64a2f3b1c9e7e12345678901');
console.log(id.getTimestamp());
// ISODate('2023-07-03T10:15:29.000Z')

// The first 8 hex chars = 4-byte timestamp
// 64a2f3b1 = Unix epoch seconds => 2023-07-03

// GridFS upload example (Node.js driver)
const { GridFSBucket } = require('mongodb');
const bucket = new GridFSBucket(db, { bucketName: 'uploads' });

const uploadStream = bucket.openUploadStream('photo.jpg');
fs.createReadStream('/tmp/photo.jpg').pipe(uploadStream);
uploadStream.on('finish', () => console.log('Uploaded:', uploadStream.id));

// Two documents in the same collection with different shapes
// This is perfectly valid in MongoDB

// User with social login
{ _id: ObjectId('...'), name: 'Alice', googleId: 'g_12345', createdAt: new Date() }

// User with email/password
{ _id: ObjectId('...'), name: 'Bob', email: 'bob@test.com', passwordHash: 'bcrypt...', createdAt: new Date() }

// mongosh: insert and read back
db.items.insertOne({ name: 'Chair', price: NumberDecimal('199.99'), createdAt: new Date() });

db.items.findOne({ name: 'Chair' });
// Output:
// {
//   _id: ObjectId('64a2f3b1...'),
//   name: 'Chair',
//   price: Decimal128('199.99'),
//   createdAt: ISODate('2024-01-15T10:23:00.000Z')
// }

const { ObjectId, Decimal128 } = require('mongodb');

// JS object -> BSON automatically by the driver
const doc = {
  _id: new ObjectId(),           // BSON ObjectId
  name: 'Widget',                // BSON String
  price: Decimal128.fromString('19.99'),  // BSON Decimal128
  stock: 100,                    // BSON Double (JS default)
  createdAt: new Date(),         // BSON Date
  tags: ['sale', 'new']          // BSON Array
};
await db.collection('products').insertOne(doc);