Is there a way to perform the `reduce(...)` operat...
# questions
b
Is there a way to perform the
reduce(...)
operation so that the input is in temporal order of events? The documentation for the reduce functions says "_There are no guarantees on the order of input._" But I see that the documentation of
groupByUser()
says "This transformation is a specialization of
groupBy()
that guarantees that the reduce function(s) will process all events of a single user in temporal order."
My question is how do I present the input to the
reduce
function in a temporal order of events for a custom
groupBy()
(essentially how does the
groupByUser()
able to achieve this?)