incubator-cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Alain RODRIGUEZ <arodr...@gmail.com>
Subject Re: how-to scan a table using CQL3
Date Mon, 26 Aug 2013 14:51:02 GMT
Furthermore I think this is already available on the 1.2.8. Not tested yet.


2013/8/26 Keith Wright <kwright@nanigans.com>

> I noticed in C* 2.0 that it will support automatic paging for CQL queries (
> https://issues.apache.org/jira/browse/CASSANDRA-4415).  I'm wondering if
> this will make future table scans as simple as "select * from <table>".
>  Anyone try this yet?
>
> From: Alain RODRIGUEZ <arodrime@gmail.com>
> Reply-To: "user@cassandra.apache.org" <user@cassandra.apache.org>
> Date: Thursday, August 22, 2013 11:01 AM
> To: "user@cassandra.apache.org" <user@cassandra.apache.org>
> Subject: Re: how-to scan a table using CQL3
>
> Oops, I made a mistake thought I was paging on partition key when I
> actually was paging on columns. No need of token and columns are ordered.
> Sorry about bothering the ones who read this, it was a PEBCAK.
>
> Alain
>
>
>
>
> 2013/8/21 Alain RODRIGUEZ <arodrime@gmail.com>
>
>> 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:
>>>
>>>
>>>
>>>
>>>
>>
>

Mime
View raw message