MongoDB”s update() and save() methods are used to update document into a collection. The update() method updates the values in the existing document while the save() method replaces the existing document with the document passed in save() method.

MongoDB Update() Method

The update() method updates the values in the existing document.

Syntax

The basic syntax of update() method is as follows −

>db.COLLECTION_NAME.update(SELECTION_CRITERIA, UPDATED_DATA)

Example

Consider the mycol collection has the following data.

{ "_id" : ObjectId(5983548781331adf45ec5), "title":"MongoDB Overview"}
{ "_id" : ObjectId(5983548781331adf45ec6), "title":"NoSQL Overview"}
{ "_id" : ObjectId(5983548781331adf45ec7), "title":"Tutorials Point Overview"}

Following example will set the new title ”New MongoDB Tutorial” of the documents whose title is ”MongoDB Overview”.

>db.mycol.update({''title'':''MongoDB Overview''},{$set:{''title'':''New MongoDB Tutorial''}})
WriteResult({ "nMatched" : 1, "nUpserted" : 0, "nModified" : 1 })
>db.mycol.find()
{ "_id" : ObjectId(5983548781331adf45ec5), "title":"New MongoDB Tutorial"}
{ "_id" : ObjectId(5983548781331adf45ec6), "title":"NoSQL Overview"}
{ "_id" : ObjectId(5983548781331adf45ec7), "title":"Tutorials Point Overview"}
>

By default, MongoDB will update only a single document. To update multiple documents, you need to set a parameter ”multi” to true.

>db.mycol.update({''title'':''MongoDB Overview''},
   {$set:{''title'':''New MongoDB Tutorial''}},{multi:true})

MongoDB Save() Method

The save() method replaces the existing document with the new document passed in the save() method.

Syntax

The basic syntax of MongoDB save() method is shown below −

>db.COLLECTION_NAME.save({_id:ObjectId(),NEW_DATA})

Example

Following example will replace the document with the _id ”5983548781331adf45ec5”.

>db.mycol.save(
   {
      "_id" : ObjectId("507f191e810c19729de860ea"), 
		"title":"Tutorials Point New Topic",
      "by":"Tutorials Point"
   }
)
WriteResult({
	"nMatched" : 0,
	"nUpserted" : 1,
	"nModified" : 0,
	"_id" : ObjectId("507f191e810c19729de860ea")
})
>db.mycol.find()
{ "_id" : ObjectId("507f191e810c19729de860e6"), "title":"Tutorials Point New Topic",
   "by":"Tutorials Point"}
{ "_id" : ObjectId("507f191e810c19729de860e6"), "title":"NoSQL Overview"}
{ "_id" : ObjectId("507f191e810c19729de860e6"), "title":"Tutorials Point Overview"}
>

MongoDB findOneAndUpdate() method

The findOneAndUpdate() method updates the values in the existing document.

Syntax

The basic syntax of findOneAndUpdate() method is as follows −

>db.COLLECTION_NAME.findOneAndUpdate(SELECTIOIN_CRITERIA, UPDATED_DATA)

Example

Assume we have created a collection named empDetails and inserted three documents in it as shown below −

> db.empDetails.insertMany(
	[
		{
			First_Name: "Radhika",
			Last_Name: "Sharma",
			Age: "26",
			e_mail: "[email protected]",
			phone: "9000012345"
		},
		{
			First_Name: "Rachel",
			Last_Name: "Christopher",
			Age: "27",
			e_mail: "[email protected]",
			phone: "9000054321"
		},
		{
			First_Name: "Fathima",
			Last_Name: "Sheik",
			Age: "24",
			e_mail: "[email protected]",
			phone: "9000054321"
		}
	]
)

Following example updates the age and email values of the document with name ”Radhika”.

> db.empDetails.findOneAndUpdate(
	{First_Name: ''Radhika''},
	{ $set: { Age: ''30'',e_mail: ''[email protected]''}}
)
{
	"_id" : ObjectId("5dd6636870fb13eec3963bf5"),
	"First_Name" : "Radhika",
	"Last_Name" : "Sharma",
	"Age" : "30",
	"e_mail" : "[email protected]",
	"phone" : "9000012345"
}

MongoDB updateOne() method

This methods updates a single document which matches the given filter.

Syntax

The basic syntax of updateOne() method is as follows −

>db.COLLECTION_NAME.updateOne(<filter>, <update>)

Example

> db.empDetails.updateOne(
	{First_Name: ''Radhika''},
	{ $set: { Age: ''30'',e_mail: ''[email protected]''}}
)
{ "acknowledged" : true, "matchedCount" : 1, "modifiedCount" : 0 }
>

MongoDB updateMany() method

The updateMany() method updates all the documents that matches the given filter.

Syntax

The basic syntax of updateMany() method is as follows −

>db.COLLECTION_NAME.update(<filter>, <update>)

Example

> db.empDetails.updateMany(
	{Age:{ $gt: "25" }},
	{ $set: { Age: ''00''}}
)
{ "acknowledged" : true, "matchedCount" : 2, "modifiedCount" : 2 }

You can see the updated values if you retrieve the contents of the document using the find method as shown below −

> db.empDetails.find()
{ "_id" : ObjectId("5dd6636870fb13eec3963bf5"), "First_Name" : "Radhika", "Last_Name" : "Sharma", "Age" : "00", "e_mail" : "[email protected]", "phone" : "9000012345" }
{ "_id" : ObjectId("5dd6636870fb13eec3963bf6"), "First_Name" : "Rachel", "Last_Name" : "Christopher", "Age" : "00", "e_mail" : "[email protected]", "phone" : "9000054321" }
{ "_id" : ObjectId("5dd6636870fb13eec3963bf7"), "First_Name" : "Fathima", "Last_Name" : "Sheik", "Age" : "24", "e_mail" : "[email protected]", "phone" : "9000054321" }
>