Specify Fields To Return

Sample Data

The examples in this guide use the restaurants collection in the sample_restaurants database from the Atlas sample datasets. To access this collection from your PHP application, instantiate a MongoDB\Client that connects to an Atlas cluster and assign the following value to your $collection variable:

$collection = $client->sample_restaurants->restaurants;

To learn how to create a free MongoDB Atlas cluster and load the sample datasets, see the Get Started with Atlas guide.

Specify Fields to Include

To specify the fields to include in the result, pass an options array to the MongoDB\Collection::findOne() or MongoDB\Collection::find() method that sets the projection option. Use the following syntax to set this option:

$options = [
    'projection' => [
        '<field name>' => 1,
    ],
];

The following example creates an options array and sets the projection option to return only the name, cuisine, and borough fields of matching documents. It then calls the find() method to find all restaurants in which the name field value is 'Emerald Pub', passing the options array as a parameter to find():

$options = [
    'projection' => [
        'name' => 1,
        'cuisine' => 1,
        'borough' => 1,
    ],
];
$cursor = $collection->find(['name' => 'Emerald Pub'], $options);
foreach ($cursor as $doc) {
    echo json_encode($doc), PHP_EOL;
}

{"_id":{"$oid":"..."},"borough":"Manhattan","cuisine":"American","name":"Emerald Pub"}
{"_id":{"$oid":"..."},"borough":"Queens","cuisine":"American","name":"Emerald Pub"}

When you use a projection to specify fields to include in the return document, the _id field is also included by default. All other fields are implicitly excluded. To remove the _id field from the return document, you must explicitly exclude it.

Exclude the _id Field

When specifying fields to include, you can also exclude the _id field from the returned document.

The following example performs the same query as the preceding example but excludes the _id field from the projection:

$options = [
    'projection' => [
        '_id' => 0,
        'name' => 1,
        'cuisine' => 1,
        'borough' => 1,
    ],
];
$cursor = $collection->find(['name' => 'Emerald Pub'], $options);
foreach ($cursor as $doc) {
    echo json_encode($doc), PHP_EOL;
}

{"borough":"Manhattan","cuisine":"American","name":"Emerald Pub"}
{"borough":"Queens","cuisine":"American","name":"Emerald Pub"}

Specify Fields to Exclude

To specify the fields to exclude from the result, pass an options array to the MongoDB\Collection::findOne() or MongoDB\Collection::find() method that sets the projection option. Use the following syntax to set this option:

$options = [
    'projection' => [
        '<field name>' => 0,
    ],
];

The following example creates an options array and sets the projection option to exclude the grades and address fields of matching documents. It then calls the find() method to find all restaurants in which the name field value is 'Emerald Pub', passing the options array as a parameter to find():

$options = [
    'projection' => [
        'grades' => 0,
        'address' => 0,
    ],
];
$cursor = $collection->find(['name' => 'Emerald Pub'], $options);
foreach ($cursor as $doc) {
    echo json_encode($doc), PHP_EOL;
}

{"_id":{"$oid":"..."},"borough":"Manhattan","cuisine":"American",
"name":"Emerald Pub","restaurant_id":"40367329"}
{"_id":{"$oid":"..."},"borough":"Queens","cuisine":"American",
"name":"Emerald Pub","restaurant_id":"40668598"}

When you use a projection to specify which fields to exclude, any unspecified fields are implicitly included in the return document.

API Documentation

To learn more about any of the methods or types discussed in this guide, see the following API documentation:

• MongoDB\Collection::findOne()

• MongoDB\Collection::find()