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From 안정아 <jungah....@samsung.com>
Subject Trouble implementing CAS operation with LWT query
Date Wed, 22 Feb 2017 13:42:18 GMT
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<P>Hi, all</P>
<P>&nbsp;</P>
<P>I'm trying to implement a typical CAS operation with LWT query(conditional update).
</P>
<P>But I'm having trouble keeping integrity of the result when WriteTimeoutException
occurs. </P>
<P>according to <A href="http://www.datastax.com/dev/blog/cassandra-error-handling-done-right">http://www.datastax.com/dev/blog/cassandra-error-handling-done-right</A>
</P>
<P>"If the paxos phase fails, the driver will throw a WriteTimeoutException with a WriteType.</P>
<P>CAS as retrieved with WriteTimeoutException#getWriteType().</P>
<P>In this situation you can’t know if the CAS operation has been applied..." </P>
<P>1) Doesn't it ruin the whole point of using LWT for CAS operation if you can't be
sure whether the query is applied or not? </P>
<P>2-1) Is there anyway to know whether the query is applied when timeout occurred?
</P>
<P>2-2) If we can't tell, are there any way to workaround this and keep the CAS integrity?</P>
<P>&nbsp;</P>
<P>Thanks!</P><table id=bannersignimg><tr><td><p>&nbsp;</p>
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