How to delete documents in mongodb

MongoDB provides a variety of document deletion methods: Delete a single document: Use the deleteOne() method to specify a query object. Delete multiple documents: Use the deleteMany() method to specify a query object. Delete the entire collection: Use the drop() method. Delete document using index: Use the findOneAndDelete() method to specify a query object and return the deleted document. Delete embedded documents: Use the $unset update operator to set the embedded document field to null.

How to delete a document using MongoDB

MongoDB provides several ways to delete documents in a collection.

Delete a single document

To delete a single document, you can use deleteOne() method. This method accepts a query object that specifies the document to be deleted. For example:

 <code class="shell">db.collection.deleteOne({ _id: ObjectId("5f21489c0cf8d519bcb89573") });</code>

Delete multiple documents

To delete multiple documents, you can use the deleteMany() method. This method also accepts a query object that specifies the document to be deleted. For example:

 <code class="shell">db.collection.deleteMany({ age: { $gt: 30 } });</code>

Delete the entire collection

To delete the entire collection and all its documents, you can use drop() method. For example:

 <code class="shell">db.collection.drop();</code>

Use index to delete documents

If an index is created on the field, you can quickly delete the document using the findOneAndDelete() method. This method accepts a query object, specifies the document to be deleted, and returns the deleted document. For example:

 <code class="shell">db.collection.findOneAndDelete({ name: "John" });</code>

Delete embedded documents

To delete an embedded document, you can use unset to update the operator. This operator sets the fields of the embedded document to null , effectively deleting the document. For example:

 <code class="shell">db.collection.updateOne( { _id: ObjectId("5f21489c0cf8d519bcb89573") }, { $unset: { "address.city": 1 } } );</code>

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