Copy/Clone a Database in MongoDB

In earlier versions of MongoDB, you could use the copyDB command or its helper method, db.copyDatabase() to copy a database.

MongoDB has since deprecated these. Also, starting in version 4.2, MongoDB has removed the copydb command, and therefore also the db.copyDatabase() method, which means that you can’t use them even if you wanted to if you’re using MongoDB 4.2 or later.

Fortunately, there’s another way to copy a MongoDB database.

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Copy/Clone a Collection in MongoDB

In earlier versions of MongoDB, you could use the db.collection.copyTo() method to copy a collection.

MongoDB has since deprecated that method. Also, starting in version 4.2, MongoDB has removed the eval command. Given db.collection.copyTo() wraps eval, this means that you can’t use either of them if you’re using MongoDB 4.2 or later.

Fortunately, there’s another way to copy a MongoDB collection.

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2 Ways to Delete a Collection in MongoDB

If you no longer need a collection in MongoDB, you can delete it.

Actually, the term for deleting a collection is to drop the collection.

Either way, here are two ways to delete/drop a collection when using the mongo shell.

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4 Ways to List the Collections in a MongoDB Database

When using MongoDB, there’s more than one way to list the collections in a database.

Here are four ways to get a list of collections in a MongoDB database:

  • The show collections Command
  • The listCollections Command
  • The db.getCollectionNames() Method
  • The db.getCollectionInfos() Method

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