Class Collection<TSchema>

Execute an aggregation framework pipeline against the collection, needs MongoDB >= 2.2

Perform a bulkWrite operation without a fluent API

Legal operation types are

• insertOne
• replaceOne
• updateOne
• updateMany
• deleteOne
• deleteMany

If documents passed in do not contain the _id field, one will be added to each of the documents missing it by the driver, mutating the document. This behavior can be overridden by setting the forceServerObjectId flag.

Throws

MongoDriverError if operations is not an array

An estimated count of matching documents in the db to a filter.

NOTE: This method has been deprecated, since it does not provide an accurate count of the documents in a collection. To obtain an accurate count of documents in the collection, use Collection#countDocuments| countDocuments. To obtain an estimated count of all documents in the collection, use Collection#estimatedDocumentCount| estimatedDocumentCount.

Deprecated

use Collection#countDocuments| countDocuments or Collection#estimatedDocumentCount| estimatedDocumentCount instead

Gets the number of documents matching the filter. For a fast count of the total documents in a collection see Collection#estimatedDocumentCount| estimatedDocumentCount. Note: When migrating from Collection#count| count to Collection#countDocuments| countDocuments the following query operators must be replaced:

See

• https://docs.mongodb.com/manual/reference/operator/query/expr/
• https://docs.mongodb.com/manual/reference/operator/query/geoWithin/
• https://docs.mongodb.com/manual/reference/operator/query/center/#op._S_center
• https://docs.mongodb.com/manual/reference/operator/query/centerSphere/#op._S_centerSphere

Creates an index on the db and collection collection.

Example

const collection = client.db('foo').collection('bar');

await collection.createIndex({ a: 1, b: -1 });

// Alternate syntax for { c: 1, d: -1 } that ensures order of indexes
await collection.createIndex([ [c, 1], [d, -1] ]);

// Equivalent to { e: 1 }
await collection.createIndex('e');

// Equivalent to { f: 1, g: 1 }
await collection.createIndex(['f', 'g'])

// Equivalent to { h: 1, i: -1 }
await collection.createIndex([ { h: 1 }, { i: -1 } ]);

// Equivalent to { j: 1, k: -1, l: 2d }
await collection.createIndex(['j', ['k', -1], { l: '2d' }])

Creates multiple indexes in the collection, this method is only supported for MongoDB 2.6 or higher. Earlier version of MongoDB will throw a command not supported error.

Note: Unlike Collection#createIndex| createIndex, this function takes in raw index specifications. Index specifications are defined here.

Example

const collection = client.db('foo').collection('bar');
await collection.createIndexes([
  // Simple index on field fizz
  {
    key: { fizz: 1 },
  }
  // wildcard index
  {
    key: { '$**': 1 }
  },
  // named index on darmok and jalad
  {
    key: { darmok: 1, jalad: -1 }
    name: 'tanagra'
  }
]);

Delete multiple documents from a collection

Delete a document from a collection

The distinct command returns a list of distinct values for the given key across a collection.

Drop the collection from the database, removing it permanently. New accesses will create a new collection.

Drops an index from this collection.

Drops all indexes from this collection.

Gets an estimate of the count of documents in a collection using collection metadata. This will always run a count command on all server versions.

due to an oversight in versions 5.0.0-5.0.8 of MongoDB, the count command, which estimatedDocumentCount uses in its implementation, was not included in v1 of the Stable API, and so users of the Stable API with estimatedDocumentCount are recommended to upgrade their server version to 5.0.9+ or set apiStrict: false to avoid encountering errors.

See

Behavior

Creates a cursor for a filter that can be used to iterate over results from MongoDB

Fetches the first document that matches the filter

Find a document and delete it in one atomic operation. Requires a write lock for the duration of the operation.

Find a document and replace it in one atomic operation. Requires a write lock for the duration of the operation.

Find a document and update it in one atomic operation. Requires a write lock for the duration of the operation.

Checks if one or more indexes exist on the collection, fails on first non-existing index

Retrieves this collections index info.

Retrieve all the indexes on the collection.

Initiate an In order bulk write operation. Operations will be serially executed in the order they are added, creating a new operation for each switch in types.

Throws

MongoNotConnectedError

Remarks

NOTE: MongoClient must be connected prior to calling this method due to a known limitation in this legacy implementation. However, collection.bulkWrite() provides an equivalent API that does not require prior connecting.

Initiate an Out of order batch write operation. All operations will be buffered into insert/update/remove commands executed out of order.

Throws

MongoNotConnectedError

Remarks

NOTE: MongoClient must be connected prior to calling this method due to a known limitation in this legacy implementation. However, collection.bulkWrite() provides an equivalent API that does not require prior connecting.

Inserts an array of documents into MongoDB. If documents passed in do not contain the _id field, one will be added to each of the documents missing it by the driver, mutating the document. This behavior can be overridden by setting the forceServerObjectId flag.

Inserts a single document into MongoDB. If documents passed in do not contain the _id field, one will be added to each of the documents missing it by the driver, mutating the document. This behavior can be overridden by setting the forceServerObjectId flag.

Returns if the collection is a capped collection

Get the list of all indexes information for the collection.

Returns the options of the collection.

Rename the collection.

Remarks

This operation does not inherit options from the Db or MongoClient.

Replace a document in a collection with another document

Get all the collection statistics.

Update multiple documents in a collection

Update a single document in a collection

Create a new Change Stream, watching for new changes (insertions, updates, replacements, deletions, and invalidations) in this collection.

Remarks

watch() accepts two generic arguments for distinct use cases:

• The first is to override the schema that may be defined for this specific collection
• The second is to override the shape of the change stream document entirely, if it is not provided the type will default to ChangeStreamDocument of the first argument

Example

By just providing the first argument I can type the change to be ChangeStreamDocument<{ _id: number }>

collection.watch<{ _id: number }>()
  .on('change', change => console.log(change._id.toFixed(4)));

Example

Passing a second argument provides a way to reflect the type changes caused by an advanced pipeline. Here, we are using a pipeline to have MongoDB filter for insert changes only and add a comment. No need start from scratch on the ChangeStreamInsertDocument type! By using an intersection we can save time and ensure defaults remain the same type!

collection
  .watch<Schema, ChangeStreamInsertDocument<Schema> & { comment: string }>([
    { $addFields: { comment: 'big changes' } },
    { $match: { operationType: 'insert' } }
  ])
  .on('change', change => {
    change.comment.startsWith('big');
    change.operationType === 'insert';
    // No need to narrow in code because the generics did that for us!
    expectType<Schema>(change.fullDocument);
  });