Is there a limitation on nesting of of Window Queries? I have a query
where I am using an event stream, and the changing of a value to indicate
an event. (The state goes from disconnected, to charging, to complete, it
reports many times in each of those states, but I am using lag(state, 1)
over (order by event_ts) to find those records where current record is say
complete and previous record was charging to indicate that the state has
changed.
This works well.
Now I am trying to take that result set, and do another window to find the
delta time between when the charging started and when the charging
completed, you would think that a nested query showing the state change
times, and then a select lag(event_ts, 1) over (order by event_ts) would be
able to get me both the current time (when the charging was complete) and
the previous record event_ts (when the charging started as outputted by the
subquery). However, I am getting a verbose confusing error that perhaps we
can help figure out...
The first part is:
SYSTEM ERROR: CannotPlanException: Node
[rel#92358:Subset#11.LOGICAL.ANY([]).[3]] could not be implemented;
planner state:
Root: rel#92358:Subset#11.LOGICAL.ANY([]).[3]
Original rel:
The rest is pages of information related to the query, the data etc. I
can send that separately if you are interested.
I guess, before sending all of that, are nested window queries just
not alloweable?
If that is the case, what are some alternative approaches?
Thanks,
John
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