I want to understand more deeply about LS optimization mechanism in sending MERGE snapshot to client.

If I update null value to 'f3' field, when sending snapshot, does LS send full pairs of <fieldname, value> to client (as your example: f1:value1, f2:value2, f3:null) or just has-value pairs (f1:value1, f2:value2) and ignore null-value field?