Find queries a collection using the msg.payload as the query statement as per the .find() function. Optionally, you may also (via a function) set a msg.projection object to constrain the returned fields, a msg.sort object and a msg.limit object.
Count returns a count of the number of documents in a collection or matching a query using the msg.payload as the query statement.
Aggregate provides access to the aggregation pipeline using the msg.payload as the pipeline array.
-You can override the collection the method is performed on by setting msg.collection to the desired collection name.
+You can either set the collection method in the node config or on msg.collection. Setting it in the node will override msg.collection.
See the MongoDB collection methods docs for examples.
The result is returned in msg.payload.