incubator-cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Tyler Hobbs <ty...@datastax.com>
Subject Re: Row iteration over indexed clause
Date Wed, 14 Mar 2012 20:32:19 GMT
Are you writing a new client for a language that doesn't have good
drivers?  If not, most of the existing clients already break up the query
into chunks, I think.

The pycassa implementation of this might be a useful reference:
https://github.com/pycassa/pycassa/blob/master/pycassa/columnfamily.py#L561

On Wed, Mar 14, 2012 at 2:35 AM, aaron morton <aaron@thelastpickle.com>wrote:

> If you want 100 results per call, ask for 101. Use the first 100, when you
> get to the 101'st do not examine it's data. Instead use it's key as the
> start to get the next 101.
>
> Cheers
>
> -----------------
> Aaron Morton
> Freelance Developer
> @aaronmorton
> http://www.thelastpickle.com
>
> On 14/03/2012, at 2:03 AM, Vivek Mishra wrote:
>
> Thanks.
>
> *Attribute*
> *Type*
> *Default*
> *Required*
> *Description*
> expressions
> list<IndexExpression>
> n/a
> Y
> The list of IndexExpression objects which must contain one EQ
> IndexOperator among the expressions
>  start_key
> binary
> n/a
> Y
> Start the index query at the specified key - can be set to '', i.e., an
> empty byte array, to start with the first key
>  count
> integer
> 100
> Y
> The number of results to which the index query will be constrained
>
>
>
> How do i iterate using it? How do i ensure that it should not return me
> previous results(without i need to keep something in-memory)?
>
> This is the method i am looking into:
>
> get_indexed_slices(ColumnParent column_parent, IndexClause index_clause,
> SlicePredicate column_predicate, ConsistencyLevel consistency_level)
>
> It does not have anything like count.
>
>
> Thanks,
> Vivek
>
> On Tue, Mar 13, 2012 at 6:24 PM, Shimi Kiviti <shimi.k@gmail.com> wrote:
>
>> Yes. use get_indexed_slices (http://wiki.apache.org/cassandra/API)
>> On Tue, Mar 13, 2012 at 2:12 PM, Vivek Mishra <mishra.vivs@gmail.com>wrote:
>>
>>> Hi,
>>> Is it possible to iterate and fetch in chunks using thrift API by
>>> querying using "secondary indexes"?
>>>
>>> -Vivek
>>>
>>
>>
>
>


-- 
Tyler Hobbs
DataStax <http://datastax.com/>

Mime
View raw message