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• Definition
• Behavior
• Example

Definition

db.collection. copyTo ( newCollection )

Deprecated since version 3.0.

Copies all documents from collection into newCollection using server-side JavaScript. If newCollection does not exist, MongoDB creates it.

If authorization is enabled, you must have access to all actions on all resources in order to run db.collection.copyTo(). Providing such access is not recommended, but if your organization requires a user to run db.collection.copyTo(), create a role that grants anyAction on anyResource. Do not assign this role to any other user.

Parameter	Type	Description
newCollection	string	The name of the collection to write data to.

Warning

When using db.collection.copyTo() check field types to ensure that the operation does not remove type information from documents during the translation from BSON to JSON.

The db.collection.copyTo() method uses the eval command internally. As a result, the db.collection.copyTo() operation takes a global lock that blocks all other read and write operations until the db.collection.copyTo() completes.

copyTo() returns the number of documents copied. If the copy fails, it throws an exception.

Behavior

Because copyTo() uses eval internally, the copy operations will block all other operations on the mongod instance.

Example

The following operation copies all documents from the source collection into the target collection.

db.source.copyTo(target)