db.collection.dataSize()

db.collection.dataSize()

Important

mongosh Method

This is a mongosh method. This is not the documentation for Node.js or other programming language specific driver methods.

In most cases, mongosh methods work the same way as the legacy mongo shell methods. However, some legacy methods are unavailable in mongosh.

For the legacy mongo shell documentation, refer to the documentation for the corresponding MongoDB Server release:

• mongo shell v4.4

• mongo shell v4.2

• mongo shell v4.0

For MongoDB API drivers, refer to the language specific MongoDB driver documentation.

Returns:	The size in bytes of the collection. Data compression does not affect this value.

This method provides a wrapper around the size output of the collStats (i.e. db.collection.stats()) command.

Starting in MongoDB 4.4, to run on a replica set member, collStats operations require the member to be in PRIMARY or SECONDARY state. If the member is in another state, such as STARTUP2, the operation errors.

In previous versions, the operations also run when the member is in STARTUP2. The operations wait until the member transitioned to RECOVERING.