cursor.addOption()
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Definition
cursor.addOption(flag)
Important
mongo Shell Method
This page documents the
mongo
shell method, and does not refer to the MongoDB Node.js driver (or any other driver) method. For corresponding MongoDB driver API, refer to your specific MongoDB driver documentation instead.Note
Deprecated since v3.2
Starting in v3.2, the
cursor.addOption()
operator is deprecated in themongo
shell. In themongo
shell, use available cursor methods instead.Adds
OP_QUERY
wire protocol flags, such as thetailable
flag, to change the behavior of queries.The
cursor.addOption()
method has the following parameter:ParameterTypeDescriptionflag
flagOP_QUERY
wire protocol flag. For themongo
shell, you can use the cursor flags listed below. For the driver-specific list, see your driver documentation.
Flags
The mongo
shell provides several additional cursor flags to
modify the behavior of the cursor.
Flag | Description |
---|---|
Sets the cursor not to close once the last data is
received, allowing the query to continue returning data added
after the initial results were exhausted. | |
Allows querying of a replica slave. | |
Prevents the server from timing out idle cursors. | |
For use with .. data:: DBQuery.Option.tailable; sets the cursor
to block and await data for a while rather than returning no
data. The cursor will return no data once the timeout has
expired. | |
Sets the cursor to return all data returned by the
query at once rather than splitting the results into batches. | |
Sets the cursor to return partial data from a query against a
sharded cluster in which some shards do not respond rather than
throwing an error. |
Example
The following example adds the DBQuery.Option.tailable
flag and the
DBQuery.Option.awaitData
flag to ensure that the query returns a
tailable cursor. The sequence creates a cursor that will wait for few
seconds after returning the full result set so that it can capture and
return additional data added during the query:
var t = db.myCappedCollection; var cursor = t.find().addOption(DBQuery.Option.tailable). addOption(DBQuery.Option.awaitData)
Warning
Adding incorrect wire protocol flags can cause problems and/or extra server load.