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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Create a Collection in MongoDB

When you create a database in MongoDB, your database is basically an empty container for which you can add one or more collections to.

A collection is analogous to a table in relational databases.

In relational databases, you can use CREATE TABLE to create each table that you want in the database.

But MongoDB is not a relational database, and it stores its data as documents. Each document is stored in a collection.

This article shows you how to create a collection in MongoDB.

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