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From Vladimir Yudovin <>
Subject Re: Can a Select Count(*) Affect Writes in Cassandra?
Date Thu, 10 Nov 2016 09:02:14 GMT
Hi Shalom,

so not sure, but probably excessive memory consumption by this SELECT causes C* to flush tables
to free memory. 

Best regards, Vladimir Yudovin, 

Winguzone - Hosted Cloud Cassandra
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---- On Thu, 10 Nov 2016 03:36:59 -0500Shalom Sagges &lt;;
wrote ----

Hi There!

I'm using C* 2.0.14. 

I experienced a scenario where a "select count(*)" that ran every minute on a table with practically
no results limit (yes, this should definitely be avoided), caused a huge increase in Cassandra
writes to around 150 thousand writes per second for that particular table.

Can anyone explain this behavior? Why would a Select query significantly increase write count
in Cassandra?



Shalom Sagges


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