$natural¶

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Definition
Behavior
Examples
Additional Information

Definition¶

$natural¶

Use the $natural operator to use natural order for the results of a sort operation. Natural order refers to the logical ordering of documents internally within the database.

The $natural operator uses the following syntax to return documents in the order they exist on disk:

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db.collection.find().sort( { $natural: 1 } )

Behavior¶

On a sharded collection the $natural operator returns a collection scan sorted in natural order, the order the database inserts and stores documents on disk.

You cannot specify $natural sort order if the query includes a $text expression.

Examples¶

Reverse Order¶

Use -1 to return documents in the reverse order as they occur on disk:

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db.collection.find().sort( { $natural: -1 } )

Natural Order Comparison¶

To demonstrate natural ordering:

Create an { normal: 1 } index on a collection (e.g. coll).
Insert relevant objects with _id and normal values, for example, a document with _id and normal fields that both hold the same string:
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```
db.coll.insert( { _id: "01", normal: "01" } )
```
Use values with different types for each document, but both fields in the document should have the same value:
Use .find().sort().explain() for all operations.

This scenario returns these results when using find() for different _id values; sorting with the $natural operator, _id index, and normal index; and a description of the explain() method output:

		`sort()`
`find()`	`$natural`:1	_id:1	normal:1
_id:ObjectId()	`explain()` used B-Tree cursor	`explain()` used B-Tree cursor	`explain()` used B-Tree cursor
_id:Object()	`explain()` used B-Tree cursor	`explain()` used B-Tree cursor	`explain()` used B-Tree cursor
_id:string()	`explain()` used B-Tree cursor	`explain()` used B-Tree cursor	`explain()` used B-Tree cursor
_id:integer()	`explain()` used B-Tree cursor	`explain()` used B-Tree cursor	`explain()` used B-Tree cursor
_id:BinData()	`explain()` scanned entire collection	`explain()` used B-Tree cursor	`explain()` used B-Tree cursor
normal:(any query)	`explain()` scanned entire collection	`explain()` used B-Tree cursor	`explain()` used B-Tree cursor

Additional Information¶

cursor.sort()

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