Difference between count() and find().count() in MongoDB?


There is no difference between count() and find().count(). Let us see how both of them works. To understand the concept, let us create a collection with the document. The query to create a collection with a document is as follows −

> db.countDemo.insertOne({"UserId":1,"UserName":"John"});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5c7f9d278d10a061296a3c5d")
}
> db.countDemo.insertOne({"UserId":2,"UserName":"Carol"});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5c7f9d308d10a061296a3c5e")
}
> db.countDemo.insertOne({"UserId":3,"UserName":"Bob"});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5c7f9d3a8d10a061296a3c5f")
}
> db.countDemo.insertOne({"UserId":4,"UserName":"Mike"});
{
   "acknowledged" : true,
   "insertedId" : ObjectId("5c7f9d428d10a061296a3c60")
}

Display all documents from a collection with the help of find() method. The query is as follows −

> db.countDemo.find().pretty();

The following is the output −

{
   "_id" : ObjectId("5c7f9d278d10a061296a3c5d"),
   "UserId" : 1,
   "UserName" : "John"
}
{
   "_id" : ObjectId("5c7f9d308d10a061296a3c5e"),
   "UserId" : 2,
   "UserName" : "Carol"
}
{
   "_id" : ObjectId("5c7f9d3a8d10a061296a3c5f"),
   "UserId" : 3,
   "UserName" : "Bob"
}
{
   "_id" : ObjectId("5c7f9d428d10a061296a3c60"),
   "UserId" : 4,
   "UserName" : "Mike"
}

Here is the query for count() that counts the number of records −

> db.countDemo.count();

The following is the output −

4

Here is the query for find().count(). The query is as follows −

> db.countDemo.find().count();

The following is the output −

4

Updated on: 30-Jul-2019

261 Views

Kickstart Your Career

Get certified by completing the course

Get Started
Advertisements