What's the difference between insert(), insertOne(), and insertMany() method?

Question

What\'s the difference between insert(), insertOne(), and insertMany() methods on MongoDB. In what situation should I use each one?

Answer 1

1. db.collection.insert():

   It allows you to insert One or more documents in the collection. Syntax:

   • Single insert: db.collection.insert({});

   • Multiple insert:

     db.collection.insert([ , , ... ]);

   Returns a WriteResult object: WriteResult({ "nInserted" : 1 });

2. db.collection.insertOne():

   It allows you to insert exactly 1 document in the collection. Its syntax is the same as that of single insert in insert().

   Returns the following document:

   {
      "acknowledged" : true,
      "insertedId" : ObjectId("56fc40f9d735c28df206d078")
   }
   

3. db.collection.insertMany():

   It allows you to insert an array of documents in the collection. Syntax:

   db.collection.insertMany(
       { [  , , ... ] });
   

   Returns the following document:

   {
      "acknowledged" : true,
      "insertedIds" : [
         ObjectId("562a94d381cb9f1cd6eb0e1a"),
         ObjectId("562a94d381cb9f1cd6eb0e1b"),
         ObjectId("562a94d381cb9f1cd6eb0e1c")
      ]
   }
   

All three of these also allow you to define a custom writeConcern and also create a collection if it doesn't exist.