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From Sylvain Lebresne <sylv...@yakaz.com>
Subject Re: Timestamp of an entire row?
Date Fri, 11 Jun 2010 17:10:54 GMT
> Correct me if I am wrong, but I beleive a row does not have a timestamp,
> only individual columns have timestamps.

You are correct

> So for instance if I need to know when a row was last modified, would I have
> to perform a get_slice and get all columns pertaining to that row, and then
> iterate through the columns to see which timestamp is the greatest(most
> recent).

If you do this reasonably often it is probably much more efficient to
use one column
per row (you name it "lastModicationTime" or something alike) and make
it contains
the timestamp of the last modification. It means you'll have to update
this on each
write in the row (with the current time) but Cassandra is fast on write.

--
Sylvain

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