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From Alain RODRIGUEZ <arodr...@gmail.com>
Subject Re: how-to scan a table using CQL3
Date Wed, 21 Aug 2013 16:18:12 GMT
Hi, I am sorry about digging this up but I was in search of this kind of
information and read this thread.

How to make sure that the first rowkey you select has the smaller token ? I
mean when you perform "select rowkey from my_table limit N;" can you have
any data with any token or is data token ordered by default ?

I tried it in dev and I have data with bigger token, but also with smaller
token so I would have to do :

 select rowkey from my_table where token(rowkey)
> token(last_rowkey_returned) limit N;

But also :

 select rowkey from my_table where token(rowkey) <
token(last_rowkey_returned) limit N;

How to make sure you scan all your data, and only once, with CQL3 ? Am I
misunderstanding or missing something ?

Alain

2013/5/14 aaron morton <aaron@thelastpickle.com>

> select rowkey from my_table limit N;
> while some_row_is_returned do
>  select rowkey from my_table where token(rowkey) >
> token(last_rowkey_returned) limit N;
>
> That should work for you.
>
> See
> http://www.datastax.com/docs/1.2/cql_cli/using/paging#non-ordered-partitioner-paging
>
> Cheers
>
>    -----------------
> Aaron Morton
> Freelance Cassandra Consultant
> New Zealand
>
> @aaronmorton
> http://www.thelastpickle.com
>
> On 11/05/2013, at 9:23 AM, Thorsten von Eicken <tve@rightscale.com> wrote:
>
> Thanks, this is interesting, but if I'm not mistaken, Astyanax uses CQL2.
> I'm trying to find a CQL3 solution on top the binary protocol. There has to
> be a way to do this in CQL3...?
> Thorsten
>
>
>
> On 5/10/2013 1:33 PM, Keith Wright wrote:
>
> What you are proposing should work and I started to implement that using
> multiple threads over the token ranges but decided instead to use to
> Astyanax's read all rows recipe as it does much of that already.  It
> required some work to convert the composite CQL2 format returned from
> Astayanx into what is expected for CQL3 but did work.  Here's an outline
> of what you would do:
>
>
>
>
>

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