The maximum amount of time to allow the query to run.
Collation allows users to specify language-specific rules for string comparison, such as rules for letter-case and accent marks.
Users can specify an arbitrary string to help trace the operation through the database profiler, currentOp, and logs.
The maximum amount of time to allow the query to run.
Specifies the read concern. Only compatible with a write stage. (e.g. $out, $merge)