You can use updateMany() to update documents. Let us create a collection with a document. The query to create a collection with a document is as follows −
> db.updateManyDocumentsDemo.insertOne({"StudentName":"John","StudentLastName":"Smith"}); { "acknowledged" : true, "insertedId" : ObjectId("5c948edd4cf1f7a64fa4df48") } > db.updateManyDocumentsDemo.insertOne({"StudentName":"John","StudentLastName":"Doe"}); { "acknowledged" : true, "insertedId" : ObjectId("5c948ee64cf1f7a64fa4df49") } > db.updateManyDocumentsDemo.insertOne({"StudentName":"Carol","StudentLastName":"Taylor"}); { "acknowledged" : true, "insertedId" : ObjectId("5c948ef14cf1f7a64fa4df4a") } > db.updateManyDocumentsDemo.insertOne({"StudentName":"David","StudentLastName":"Miller"}); { "acknowledged" : true, "insertedId" : ObjectId("5c948f044cf1f7a64fa4df4b") }
Display all documents from a collection with the help of find() method. The query is as follows −
> db.updateManyDocumentsDemo.find().pretty();
The following is the output −
{ "_id" : ObjectId("5c948edd4cf1f7a64fa4df48"), "StudentName" : "John", "StudentLastName" : "Smith" } { "_id" : ObjectId("5c948ee64cf1f7a64fa4df49"), "StudentName" : "John", "StudentLastName" : "Doe" } { "_id" : ObjectId("5c948ef14cf1f7a64fa4df4a"), "StudentName" : "Carol", "StudentLastName" : "Taylor" } { "_id" : ObjectId("5c948f044cf1f7a64fa4df4b"), "StudentName" : "David", "StudentLastName" : "Miller" }
Here is the query to update all documents. The “StudentName” is updated with “StudentFirstName” −
> db.updateManyDocumentsDemo.updateMany({}, {$rename: {'StudentName': "StudentFirstName"}});
The following is the output −
{ "acknowledged" : true, "matchedCount" : 4, "modifiedCount" : 4 }
Check the document has been updated or not. The query is as follows −
> db.updateManyDocumentsDemo.find().pretty();
The following is the output −
{ "_id" : ObjectId("5c948edd4cf1f7a64fa4df48"), "StudentLastName" : "Smith", "StudentFirstName" : "John" } { "_id" : ObjectId("5c948ee64cf1f7a64fa4df49"), "StudentLastName" : "Doe", "StudentFirstName" : "John" } { "_id" : ObjectId("5c948ef14cf1f7a64fa4df4a"), "StudentLastName" : "Taylor", "StudentFirstName" : "Carol" } { "_id" : ObjectId("5c948f044cf1f7a64fa4df4b"), "StudentLastName" : "Miller", "StudentFirstName" : "David" }