MongoDB Delete Document

In this post, we will learn how to delete a document using MongoDB.

Delete Methods

MongoDB provides the following methods to delete documents of a collection:

• db.collection.deleteOne() - Delete at most a single document that match a specified filter even though multiple documents may match the specified filter.
• db.collection.deleteMany() - Delete all documents that match a specified filter.
• db.collection.remove() - Delete a single document or all documents that match a specified filter.

The examples on this page use the posts collection. To populate the posts collection, run the following:

db.posts.insertMany([
   {
      title: 'MongoDB Overview', 
      description: 'MongoDB is no sql database',
      by: 'Java Guides',
      url: 'https://javaguides.net',
      tags: ['mongodb', 'database', 'NoSQL'],
      likes: 100
   },
 
   {
      title: 'NoSQL Database', 
      description: "NoSQL database doesn't have tables",
       by: 'Java Guides',
      url: 'https://javaguides.net',
      tags: ['mongodb', 'database', 'NoSQL'],
      likes: 20, 
      comments: [ 
         {
            user:'user1',
            message: 'My first comment',
            dateCreated: new Date(2013,11,10,2,35),
            like: 0 
         }
      ]
   }
]);

{
        "acknowledged" : true,
        "insertedIds" : [
                ObjectId("5e18246f7695f4d696a05985"),
                ObjectId("5e18246f7695f4d696a05986")
        ]
}

Delete All Documents

To delete all documents from a collection, pass an empty filter document {} to the db.collection.deleteMany() method.

The following example deletes all documents from the inventory collection:

db.posts.deleteMany({})

The method returns a document with the status of the operation.

Delete Only One Document that Matches a Condition

To delete at most a single document that matches a specified filter (even though multiple documents may match the specified filter) use the db.collection.deleteOne() method.

The following example deletes the first document where the title is "MongoDB Overview":

db.posts.deleteOne( { title: "MongoDB Overview" } )

Delete All Documents that Match a Condition

You can specify criteria, or filters, that identify the documents to delete. The filters use the same syntax as read operations.

To specify equality conditions, use : expressions in the query filter document:

{ <field1>: <value1>, ... }

A query filter document can use the query operators to specify conditions in the following form:

{ <field1>: { <operator1>: <value1> }, ... }

To delete all documents that match deletion criteria, pass a filter parameter to the deleteMany() method.

The following example removes all documents from the inventory collection where the status field equals "A":

db.inventory.deleteMany({ by : "Java Guides" })

The method returns a document with the status of the operation.

Summary

The below diagram shows the summary of all the commands used in this post: