How to sort mongodb

MongoDB provides a sorting mechanism that sorts collections by specific fields, uses the syntax db.collection.find().sort({ field: order }) ascending/descending order, supports compound sorting by multiple fields, and recommends creating indexes to improve sorting performance.

MongoDB sorting

MongoDB provides a flexible sorting mechanism that allows you to sort documents in a collection by specific fields.

grammar

To sort MongoDB collections, use sort() method:

 <code>db.collection.find().sort({ field: order })</code>

in:

• field is the name of the field to be sorted
• order specifies the sorting order, 1 means ascending order (from minimum to maximum), -1 means descending order (from maximum to minimum)

Example

The following example sorts people collections in ascending order by name field:

 <code>db.people.find().sort({ name: 1 })</code>

The following example sorts people collections in descending order by age field:

 <code>db.people.find().sort({ age: -1 })</code>

Composite sorting

MongoDB also supports compound sorting, that is, sorting by multiple fields. To do this, pass the object containing the collation to sort() method:

 <code>db.people.find().sort({ name: 1, age: -1 })</code>

This example will sort in ascending order of name fields and in descending order of age fields if name is the same.

index

To improve sorting performance, it is recommended to create an index on the fields to be sorted. To do this, use createIndex() method:

 <code>db.people.createIndex({ name: 1 })</code>

Things to note

• Sort only affects the returned results and does not modify the actual document order in the collection.
• The complexity of the sorting operation depends on the number of documents to be sorted and the index used.
• MongoDB supports rich sorting options, including specifying specific sorting directions, ignoring case, and other advanced options.

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