You are exactly right! A few hours ago, I tried many things and finally got
the example working by defining event timestamp column before groupByKey,
just like what you suggested, but I wasn't able to figure out the reasoning
behind my fix.
val sessionUpdates = events
I was trying to find a way to resessionize features in different events based
on the event timestamps using Spark and I found a code example that uses
mapGroupsWithStateto resessionize events using processing timestamps in
their repo.
