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Message-ID: <AANLkTikEoQXXWvW9uE_o+hV-UnRM989=9B+tTtW68j9q@mail.gmail.com>
Subject: Update of value for a given name
From: A J <s5alye@gmail.com>
To: user@cassandra.apache.org
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If I update a column (i.e. change the value contents for a given name in a
given key), is the physical disk operation equivalent to delete followed by
insert.
Or is it just insert somehow making the last value marked as stale ?

In the definite guide, it says the following about SSTable:
*All writes are sequential, which is the primary reason that writes perform
so well in Cassandra. No reads or seeks of any kind are required for writing
a value to Cassandra because all writes are append operations.*
*
*
It made me wonder how updates work, if it is append only.

I am new to cassandra so please let me know if I am missing something basic.

Regards,
-AJ

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If I update a column (i.e. change the value contents for a given name in a =
given key), is the physical disk operation equivalent to delete followed by=
 insert.<div>Or is it just insert somehow making the last value marked as s=
tale ?</div>
<div><br></div><div>In the definite guide, it says the following about SSTa=
ble:</div><div><div><i>All writes are sequential, which is the primary reas=
on that writes perform so well in=A0Cassandra. No reads or seeks of any kin=
d are required for writing a value to Cassandra=A0because all writes are ap=
pend operations.</i></div>
</div><div><i><br></i></div><div>It made me wonder how updates work, if it =
is append only.</div><div><br></div><div>I am new to cassandra so please le=
t me know if I am missing something basic.</div><div><br></div><div>Regards=
,</div>
<div>-AJ</div>

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