mongodb

How to count the number of documents in a mongodb collection

I would like to know how to count the number of documents in a collection. I tried the follow

var value = collection.count();
&&
var value = collection.find().count()
&&
var value = collection.find().dataSize()

I always get method undefined.

Can you let me know what is the method to use to find the total documents in a collection.

Solution

  • If you want the number of documents in a collection, then use the count method, which returns a Promise. Here's an example:

    let coll = db.collection('collection_name');
coll.count().then((count) => {
    console.log(count);
});

    This assumes you're using Mongo 3.

    Edit: In version 4.0.3, count is deprecated. use countDocument to achieve the goal.