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Introducing MongoDB Chapter 3

This removes the entry of a user whose name is John. The output is as follows:


As you can see in the output, the deletedCount is 1 , which means the record has been


deleted.


deleteMany()

The command for deleteMany() is the same as deleteOne(). The only difference is


that deleteOne() removes only a single entry with the matched filter whereas


deleteMany() removes all the documents which match the given criteria:


> db.users.deleteMany( { name: "Jack" } )

The output is as follows:


remove()

The remove() command works to remove a single entry, as well as multiple entries, from a


collection. If we want to remove only a single document that matched certain criteria, then


we can pass the count of entries that we wish to delete. For example, let's first create an


entry:


> db.users.insertOne({ name: 'Mike', email: '[email protected]' })

With this, now we have two entries for Mike. Now, if we want to remove just one entry


using remove(), we can do so with:


> db.users.remove({ name: 'Mike' }, 1)
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