MongoDB document size can be obtained with Object.bsonsize()

For obtaining MongoDB document size, you can calculate it with Object.bsonsize().

Calculating document size with Object.bsonsize()

MongoDB document size can be calculated with Object.bsonsize(). The unit is bytes.

> db.test.insert({})
WriteResult({ "nInserted" : 1 })
> db.test.insert({ "a" : 1 })
WriteResult({ "nInserted" : 1 })
> db.test.insert({ "type" : "auto" })
WriteResult({ "nInserted" : 1 })
> db.test.insert({ "type" : "12345" })
WriteResult({ "nInserted" : 1 })

> db.test.find()
{ "_id" : ObjectId("5bf6bdef5ea78d381a18e1a5") }
{ "_id" : ObjectId("5bf6bdef5ea78d381a18e1a6"), "a" : 1 }
{ "_id" : ObjectId("5bf6bd7d5ea78d381a18e1a7"), "type" : "auto" }
{ "_id" : ObjectId("5bf6bdd95ea78d381a18e1a8"), "type" : "12345" }

> Object.bsonsize(db.test.findOne({ "_id" : ObjectId("5bf6bdef5ea78d381a18e1a9") }))
22

> Object.bsonsize(db.test.findOne({ "a" : 1 }))
33

> Object.bsonsize(db.test.findOne({ "type" : "auto" }))
37
> Object.bsonsize(db.test.findOne({ "type" : "12345" }))
38

That’s all from the Gemba where I was suddenly surprised by a MongoDB RangeError.

Calculating document size with Object.bsonsize()

References