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db.collection.dataSize()
db.collection.dataSize()
Important
mongo Shell Method
This page documents a
mongo
method. This is not the documentation for database commands or language-specific drivers, such as Node.js. To use the database command, see thesize
field returned by thecollStats
command.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.Starting in MongoDB 4.4, to run on a replica set member,
collStats
operations require the member to be inPRIMARY
orSECONDARY
state. If the member is in another state, such asSTARTUP2
, the operation errors.In previous versions, the operations also run when the member is in
STARTUP2
. The operations wait until the member transitioned toRECOVERING
.