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Message-ID: <AANLkTi=BdE6LCp8LVAa-R86TtNeQNA+QZuPbOdvM6K8G@mail.gmail.com>
Subject: New thread for : How does Cassandra handle failure during synchronous
 writes
From: Anthony John <chirayithaj@gmail.com>
To: user@cassandra.apache.org
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>>c. Read with CL = QUORUM. If read hits node1 and node2/node3, new data
that was written to node1 will be returned.

>>In this case - N1 will be identified as a discrepancy and the change will
be discarded via read repair

>>[Naren] How will Cassandra know this is a discrepancy?

Because at Q - only N1 will have the "new data" and other other nodes won't.
This lack of consistency on N! will be detected and repaired. The value that
meets Q - the values from N2-3 - will be returned.

HTH

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<span class=3D"Apple-style-span" style=3D"border-collapse: collapse; font-f=
amily: arial, sans-serif; font-size: 13px; "><div class=3D"im" style=3D"col=
or: rgb(80, 0, 80); "><div><div>&gt;&gt;c. Read with CL =3D QUORUM. If read=
 hits node1 and node2/node3, new data that was written to node1 will be ret=
urned.<br>
<br></div></div><div>&gt;&gt;In this case - N1 will be identified as a disc=
repancy and the change will be discarded via read repair</div><div><br></di=
v></div><div>&gt;&gt;[Naren] How will Cassandra know this is a discrepancy?=
</div>
<div><br></div><div>Because at Q - only N1 will have the &quot;new data&quo=
t; and other other nodes won&#39;t. This lack of consistency on N! will be =
detected and repaired. The value that meets Q - the values from N2-3 - will=
 be returned.</div>
<div><br></div><div>HTH</div></span>

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