db.collection.dataSize()

db.collection.dataSize()

Important

mongosh Method

This page documents a mongosh method. This is not the documentation for database commands or language-specific drivers, such as Node.js.

For the database command, see the size field returned by the collStats command.

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

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

mongo shell v4.4

Returns:	The size in bytes of the collection.集合的大小（以字节为单位）。Data compression数据压缩 does not affect this value.不会影响此值。

Starting in MongoDB 4.4, to run on a replica set member, collStats operations require the member to be in PRIMARY or SECONDARY state. 从MongoDB 4.4开始，要在副本集成员上运行，collStats操作要求该成员处于PRIMARY或SECONDARY状态。If the member is in another state, such as STARTUP2, the operation errors.如果成员处于其他状态，例如STARTUP2，则操作将出错。

In previous versions, the operations also run when the member is in STARTUP2. The operations wait until the member transitioned to RECOVERING.在以前的版本中，成员处于STARTUP2时也会运行这些操作。操作将等待，直到成员转换到RECOVERING。