How big can a MongoDB document be?

How big can a MongoDB document be?

16 megabytes
Document Size Limit The maximum BSON document size is 16 megabytes. The maximum document size helps ensure that a single document cannot use excessive amount of RAM or, during transmission, excessive amount of bandwidth. To store documents larger than the maximum size, MongoDB provides the GridFS API.

Why are MongoDB data files large in size?

fileSize is larger than storageSize because it includes index extents and yet-unused space in data files. While fileSize does decrease when you delete a database, fileSize does not decrease as you remove collections, documents or indexes.

How much data can be stored in a MongoDB database?

With its 16Mb limit, a MongoDB document can easily store around 2 million values of 64-bit numbers (also dates and booleans).

Does MongoDB do Sharding?

MongoDB uses sharding to support deployments with very large data sets and high throughput operations. Database systems with large data sets or high throughput applications can challenge the capacity of a single server.

What is the size of an ObjectId in MongoDB?

12 bytes
ObjectIds are small, likely unique, fast to generate, and ordered. ObjectId values are 12 bytes in length, consisting of: a 4-byte timestamp value, representing the ObjectId’s creation, measured in seconds since the Unix epoch.

How do I query large data in MongoDB?

1. Create Right indices and carefully use compound index. ( You can have max. 64 indices per collection and 31 fields in compound index)
2. Use mongo side pagination.
3. Compound index strictly follow sequence so read documentation and do trials.
4. Also try covered query for ‘summary’ like queries.

Does MongoDB need a lot space of RAM?

MongoDB requires approximately 1GB of RAM per 100.000 assets. If the system has to start swapping memory to disk, this will have a severely negative impact on performance, and should be avoided.

How do I reduce space in MongoDB?

Getting your free space back

1. Compacting individual collections. You can compact individual collections using the compact command.
2. Compacting one or more databases. For a single-node MongoDB deployment, you can use the db.
3. Compacting all databases on a server by re-syncing replica set nodes.
4. usePowerOf2Sizes.

What is MongoDB index size?

stats(1024) , is used to get size of data and size of index on user collection in MongoDB. – for bytes: no need to pass any scaling factor. – for KB: 1024, – for MB: 1024*1024, – for GB: 1024*1024*1024.

How do I shard a database in MongoDB?

MongoDB Sharding can be set up by implementing the following steps:

1. Step 1: Creating a Directory for Config Server.
2. Step 2: Starting MongoDB Instance in Configuration Mode.
3. Step 3: Starting Mongos Instance.
4. Step 4: Connecting to Mongos Instance.
5. Step 5: Adding Servers to Clusters.
6. Step 6: Enabling Sharding for Database.

What is the default size for _ID field in MongoDB?

12 byte
The default unique identifier generated as the primary key ( _id ) for a MongoDB document is an ObjectId. This is a 12 byte binary value which is often represented as a 24 character hex string, and one of the standard field types supported by the MongoDB BSON specification.

What is a BSON file?

BSON stands for Binary Javascript Object Notation. It is a binary-encoded serialization of JSON documents. BSON has been extended to add some optional non-JSON-native data types, like dates and binary data. BSON can be compared to other binary formats, like Protocol Buffers.

What is MongoDB sharding and how does it work?

Sharding is a process of splitting up the large scale of data sets into a chunk of smaller data sets across multiple MongoDB instances in a distributed environment. What is Sharding?

How can I store documents larger than the maximum size in MongoDB?

To store documents larger than the maximum size, MongoDB provides the GridFS API. See mongofiles and the documentation for your driver for more information about GridFS. MongoDB supports no more than 100 levels of nesting for BSON documents.

How do I distribute the documents in a MongoDB collection?

To distribute the documents in a collection, MongoDB partitions the collection using the shard key. The shard key consists of an immutable field or fields that exist in every document in the target collection.

How does MongoDB support horizontal scaling?

MongoDB supports horizontal scaling through sharding. A MongoDB sharded cluster consists of the following components: shard: Each shard contains a subset of the sharded data. Each shard can be deployed as a replica set. mongos: The mongos acts as a query router, providing an interface between client applications and the sharded cluster.