Compound Indexes

Overview

Compound indexes hold references to multiple fields within a collection's documents, improving query and sort performance. You can create a compound index on a collection by using the MongoDB\Collection::createIndex() method and the same syntax that you use to create single field indexes.

Create a Compound Index

Use the MongoDB\Collection::createIndex() method to create a compound index. The following example creates an index in ascending order on the title and year fields:

$indexName = $collection->createIndex(
    ['title' => 1, 'year' => 1]
);

The following is an example of a query that is covered by the index created in the preceding code example:

$document = $collection->findOne(
    ['title' => ['$regex' => 'Sunrise'],
    'year' => ['$gte' => 1990]]
);
echo json_encode($document), PHP_EOL;

{"_id":...,"title":"Before Sunrise",...,"year":1995,...}

Additional Information

To learn more about compound indexes, see Compound Indexes in the MongoDB Server manual.

To view runnable examples that demonstrate how to manage indexes, see Optimize Queries by Using Indexes.