MongoDB\Collection::findOne()
Definition
Parameters
$filter
: array|object- The filter criteria that specifies the documents to query.
$options
: arrayAn array specifying the desired options.
NameTypeDescriptionallowDiskUsebooleanEnables writing to temporary files. When set totrue
, queries can write data to the_tmp
sub-directory in thedbPath
directory.allowPartialResultsbooleanFor queries against a sharded collection, returns partial results from themongos
if some shards are unavailable instead of throwing an error.codecMongoDB\Codec\DocumentCodecThe codec to use for encoding or decoding documents. This option is mutually exclusive with the
typeMap
option.Defaults to the collection's codec. Inheritance for a default
codec
option takes precedence over that of thetypeMap
option.New in version 1.17.
collationarray|objectCollation allows users to specify language-specific rules for string comparison, such as rules for lettercase and accent marks. When specifying collation, the
locale
field is mandatory; all other collation fields are optional. For descriptions of the fields, see Collation Document.If the collation is unspecified but the collection has a default collation, the operation uses the collation specified for the collection. If no collation is specified for the collection or for the operation, MongoDB uses the simple binary comparison used in prior versions for string comparisons.
commentmixedEnables users to specify an arbitrary comment to help trace the operation through the database profiler, currentOp output, and logs.
The comment can be any valid BSON type since MongoDB 4.4. Earlier server versions only support string values.
hintstring|array|objectThe index to use. Specify either the index name as a string or the index key pattern as a document. If specified, then the query system will only consider plans using the hinted index.
New in version 1.2.
letarray|objectMap of parameter names and values. Values must be constant or closed expressions that do not reference document fields. Parameters can then be accessed as variables in an aggregate expression context (e.g.
$$var
).This is not supported for server versions prior to 5.0 and will result in an exception at execution time if used.
New in version 1.13.
maxarray|objectThe exclusive upper bound for a specific index.
New in version 1.2.
maxTimeMSintegerThe cumulative time limit in milliseconds for processing operations on the cursor. MongoDB aborts the operation at the earliest following interrupt point.
minarray|objectThe inclusive lower bound for a specific index.
New in version 1.2.
projectionarray|objectThe projection specification to determine which fields to include in the returned documents. See Project Fields to Return from Query and Projection Operators in the MongoDB manual.readConcernRead concern to use for the operation. Defaults to the collection's read concern.
It is not possible to specify a read concern for individual operations as part of a transaction. Instead, set the
readConcern
option when starting the transaction.readPreferenceRead preference to use for the operation. Defaults to the collection's read preference.
returnKeybooleanIf true, returns only the index keys in the resulting documents.
New in version 1.2.
sessionClient session to associate with the operation.
New in version 1.3.
showRecordIdbooleanDetermines whether to return the record identifier for each document. If true, adds a field
$recordId
to the returned documents.New in version 1.2.
skipintegerNumber of documents to skip. Defaults to0
.sortarray|objectThe sort specification for the ordering of the results.typeMaparrayThe type map to apply to cursors, which determines how BSON documents are converted to PHP values. Defaults to the collection's type map.
This will be used for the returned result document.
Return Values
An array or object for the first document that matched
the query, or null
if no document matched the query. The return type will
depend on the typeMap
option.
Errors/Exceptions
MongoDB\Exception\UnsupportedException
if options are used and
not supported by the selected server (e.g. collation
, readConcern
,
writeConcern
).
MongoDB\Exception\InvalidArgumentException
for errors related to
the parsing of parameters or options.
MongoDB\Driver\Exception\RuntimeException for other errors at the extension level (e.g. connection errors).
Behavior
When evaluating query criteria, MongoDB compares types and values according to its own comparison rules for BSON types, which differs from PHP's comparison and type juggling rules. When matching a special BSON type the query criteria should use the respective BSON class in the extension (e.g. use MongoDB\BSON\ObjectId to match an ObjectId).
Examples
Matching BSON Types in Query Criteria
In the following example, documents in the restaurants
collection use an
ObjectId for their identifier (the default)
and documents in the zips
collection use a string. Since ObjectId is a
special BSON type, the query criteria for selecting a restaurant must use the
MongoDB\BSON\ObjectId class.
$database = (new MongoDB\Client)->test; $zip = $database->zips->findOne(['_id' => '10036']); $restaurant = $database->restaurants->findOne([ '_id' => new MongoDB\BSON\ObjectId('594d5ef280a846852a4b3f70'), ]);
Projecting Fields
The following example finds a restaurant based on the cuisine
and
borough
fields and uses a projection to limit the fields that are
returned.
$collection = (new MongoDB\Client)->test->restaurants; $restaurant = $collection->findOne( [ 'cuisine' => 'Italian', 'borough' => 'Manhattan', ], [ 'projection' => [ 'name' => 1, 'borough' => 1, 'cuisine' => 1, ], ] ); var_dump($restaurant);
The output would then resemble:
object(MongoDB\Model\BSONDocument)#10 (1) { ["storage":"ArrayObject":private]=> array(4) { ["_id"]=> object(MongoDB\BSON\ObjectId)#8 (1) { ["oid"]=> string(24) "576023c6b02fa9281da3f983" } ["borough"]=> string(9) "Manhattan" ["cuisine"]=> string(7) "Italian" ["name"]=> string(23) "Isle Of Capri Resturant" } }
See Also
find command reference in the MongoDB manual