New in version 1.4.
- The filter criteria that specifies the documents to count.
An array specifying the desired options.NameTypeDescriptioncollationarray|objectcommentmixedhintstring|array|object
The 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.limitintegerThe maximum number of matching documents to return.maxTimeMSinteger
The cumulative time limit in milliseconds for processing operations on the cursor. MongoDB aborts the operation at the earliest following interrupt point.readConcernreadPreference
Read preference to use for the operation. Defaults to the collection's read preference.session
Client session to associate with the operation.skipintegerThe number of matching documents to skip before returning results.
The number of documents matching the filter criteria.
MongoDB\\Exception\\UnexpectedValueException if the command
response from the server was malformed.
MongoDB\\Exception\\UnsupportedException if options are used and
not supported by the selected server (e.g.
MongoDB\\Exception\\InvalidArgumentException for errors related to
the parsing of parameters or options.
MongoDB\\Driver\\Exception\\RuntimeException for other errors at the driver level (e.g. connection errors).
Internally, this method uses the
$group aggregation pipeline operator to
obtain the result. If a
filter parameter is given, this is converted into
$match pipeline operator. Optional
$limit stages are
group if present in the options.
This method counts documents on the server side. To obtain an approximate
total number of documents without filters, the
MongoDB\\Collection::estimatedDocumentCount() method can be
used. This method estimates the number of documents based on collection
metadata, thus sacrificing accuracy for performance.
Since this method uses an aggregation pipeline, some query operators accepted
filter cannot be used.
Consider the following alternatives to these restricted operators:
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 driver (e.g. use MongoDB\\BSON\\ObjectId to match an ObjectId).