CoroutineMongoCollection

A collection stores related documents together.

The Coroutine client provides a coroutine-aware API which internally uses the official Kotlin driver.

Usually, all documents in a collection have the same shape (the same fields). However, heterogeneous structure can be achieved by using:

• Kotlin collections, like List and Set, the embed an arbitrary number of items.

• Polymorphism, for example with sealed class, to have different fields based on a discriminator.

To avoid name collisions, collections are grouped into databases.

To obtain a collection, see MongoDatabase.collection.

Size limit

A MongoDB document cannot exceed 16 MiB.

You can measure the size of a document with opensavvy.ktmongo.bson.BsonDocument.toByteArray followed by ByteArray.size.

The maximum nesting is 100 levels. Each document or array adds a level.

External resources

• Official documentation

• Size limits

See also