$bsonSize
New from version 8.0.1.
The $bsonSize operator in Amazon DocumentDB returns the size in bytes of a document when encoded as BSON.
Parameters
Example (MongoDB Shell)
The following example shows how to use the $bsonSize operator to return the BSON size of each document.
Create sample documents
db.items.insertMany([
{_id: 1, name: "a", tags: ["x"]},
{_id: 2, name: "ab", tags: ["x", "y", "z"]},
{_id: 3, name: "abc", tags: []}
]);
Query example
db.items.aggregate([
{ $project: { docSize: { $bsonSize: "$$ROOT" } } }
]);
Output
[
{_id: 1, docSize: 46},
{_id: 2, docSize: 65},
{_id: 3, docSize: 39}
]
Exact sizes depend on BSON encoding of the document fields.
Code examples
To view a code example for using the $bsonSize operator, choose the tab for the language that you want to use:
- Node.js
-
const { MongoClient } = require('mongodb');
async function example() {
const client = new MongoClient('mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false');
try {
await client.connect();
const db = client.db('test');
const collection = db.collection('items');
const result = await collection.aggregate([
{ $project: { docSize: { $bsonSize: "$$ROOT" } } }
]).toArray();
console.log(result);
} finally {
await client.close();
}
}
example();
- Python
-
from pymongo import MongoClient
def example():
client = MongoClient('mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false')
try:
db = client['test']
collection = db['items']
result = list(collection.aggregate([
{'$project': {'docSize': {'$bsonSize': '$$ROOT'}}}
]))
print(result)
finally:
client.close()
example()
