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From Martin Engen <>
Subject Structured Streaming together with Cassandra Queries
Date Sat, 22 Sep 2018 09:21:24 GMT

I have a case where I am continuously getting a bunch sensor-data which is being stored into
a Cassandra table (through Kafka). Every week or so, I want to manually enter additional data
into the system - and I want this to trigger some calculations merging the manual entered
data, and the weeks worth of streaming sensor-data.

Is there a way to make dynamic Cassandra queries based on data coming into Spark?

example: Pressure sensors are being continuously stored into Cassandra, and I enter a weeks
worth of temperatures into the system at the end of the week (1 day/row at a time).
I want each of these rows to trigger queries to Cassandra to get the pressures for every specific
day, and do some calculations on this.

I have been looking at using Structured Streaming with the Cassandra-spark-connector, but
I cant find  a way to take data from a row in structured streaming into account on the query
being made. And I seem to have to query for 'everything', and then filter in Spark.

Any ideas or tips for how to solve this?

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