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From Edward Capriolo <edlinuxg...@gmail.com>
Subject Re: Offsets and Range Queries
Date Thu, 15 Nov 2012 15:33:06 GMT
There are several reasons. First there is no "absolute offset". The
rows are sorted by the data. If someone inserts new data between your
query and this query the rows have changed.

Unless you doing select queries inside a transaction with repeatable
read and your database supports this the query you mention does not
really have "absolute offsets " either. The results of the query can
change between reads.

In cassandra we do not execute large queries (that might results to
temp tables or whatever) and allow you to page them. Slices have a
fixed size, this ensures that the the "query" does not execute for
arbitrary lengths of time.


On Thu, Nov 15, 2012 at 6:39 AM, Ravikumar Govindarajan
<ravikumar.govindarajan@gmail.com> wrote:
> Usually we do a SELECT * FROM .... ORDER BY .... LIMIT 26,25 for pagination
> purpose, but specifying offset is not available for range queries in
> cassandra.
>
> I always have to specify a start-key to achieve this. Are there reasons for
> choosing such an approach rather than providing an absolute offset?
>
> --
> Ravi

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