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From Tatu Saloranta <>
Subject Re: Tree Search in Cassandra
Date Mon, 07 Jun 2010 21:30:00 GMT
On Mon, Jun 7, 2010 at 12:06 AM, David Boxenhorn <> wrote:
> I wonder if there is a robust algorithm for maintaining b-trees that doesn't
> require atomicity? How about if you create the three new super columns
> first, then attach them to the parent, then delete the old super column? If
> it fails, it would leave junk, but that could be cleaned up every once in a
> while.

I think the challenge is that beyond ordering of pieces of a single
transaction, there is the problem of concurrent ones, which may well
see incomplete states.
That is where multi-step-operations would help of course, except that
there are still read-modify parts of operations that would have to be
handled by server itself (only split if super column is 'full' etc).

-+ Tatu +-

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