Hi Julian, I know Apache Phoenix uses materialized views in calcite as a
secondary index. So a function-based index may be just a materialization of
your function that would give you the level set of the tuples you
are looking for. You would need to implement some way to look up based on
the index
Hi Ruhollah,
thanks for your mail.
Regarding your MATCH_RECOGNIZE question, I'm not sure whether this could work
or not (I'm skeptic but it is a really powerful feature).
But to your other question, the thing you describe should be a perfect fit for
what we usually do, yes.
In our situations
Hey,
Julian (H) you are right with your assumptions. But, in our situation we do not
necessarily need timestamps to be aligned on a regular grid but they have to be
ordered (for processing at least).
I think stock prices are a very good example.
Three reasons why regular grids usually don’t
Maybe this is a separate but related problem, however we see the same thing
with events in other use cases that are complex such as path analysis.
Let's say you are a cable provider and you want to identify channel
surfers. You define a channel surfer as any user that has flipped across 3
channels
I think the difficulty with JulianF’s signal processing domain is that he needs
there to be precisely one record at every clock tick (or more generally, at
every point in an N-dimensional discrete space).
Consider stock trading. A stock trade is an event that happens in continuous
time, say
I would say a similar theory applies. Some things are different when you're
dealing with streams. Mainly joins and aggregations. Semantics are
necessarily different whenever you have operations involving more than one
row at a time from the input stream. When dealing with a relation an
aggregation
Hi Michael,
yes, our workloads are usually in the context of streaming (but for replay or
so we also use batch).
But, if I understand it correctly, the same theory applies to both, tables
("relations") and streaming tables, or?
I hope to find time soon to write a PLC4X - Calicte source which
Perhaps you've thought of this already, but it sounds like streaming
relational algebra could be a good fit here.
https://calcite.apache.org/docs/stream.html
--
Michael Mior
mm...@apache.org
Le dim. 16 déc. 2018 à 18:39, Julian Feinauer
a écrit :
> Hi Calcite-devs,
>
> I just had a very
Hi Calcite-devs,
I just had a very interesting mail exchange with Julian (Hyde) on the incubator
list [1]. It was about our project CRUNCH (which is mostly about time series
analyses and signal processing) and its relation to relational algebra and I
wanted to bring the discussion to this list
