Update A Document
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" } >
Update a Single Document
The following example uses the db.collection.updateOne() method on the inventory collection to update the first document where item equals "paper":
| db.inventory.updateOne( |
| { item: “paper” }, |
| { |
| $set: { “size.uom”: “cm”, status: “P” }, |
| $currentDate: { lastModified: true } |
| } |
| ) |
The update operation:
uses the
$setoperator to update the value of thesize.uomfield to"cm"and the value of thestatusfield to"P",uses the
$currentDateoperator to update the value of thelastModifiedfield to the current date. IflastModifiedfield does not exist,$currentDatewill create the field. See$currentDatefor details.
| db.inventory.updateMany( |
| { “qty”: { $lt: 50 } }, |
| { |
| $set: { “size.uom”: “in”, status: “P” }, |
| $currentDate: { lastModified: true } |
| } |
| ) |
The update operation:
uses the
$setoperator to update the value of thesize.uomfield to"in"and the value of thestatusfield to"P",uses the
$currentDateoperator to update the value of thelastModifiedfield to the current date. IflastModifiedfield does not exist,$currentDatewill create the field. See$currentDatefor details.
| db.inventory.replaceOne( |
| { item: “paper” }, |
| { item: “paper”, instock: [ { warehouse: “A”, qty: 60 }, { warehouse: “B”, qty: 40 } ] } |
| ) |
