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From Jonathan Ellis <jbel...@gmail.com>
Subject Re: working of get_range_slices
Date Thu, 14 Oct 2010 19:16:15 GMT
I have not benchmarked this.  I suggest trying both and letting us know. :)

On Thu, Oct 14, 2010 at 2:03 PM, Narendra Sharma
<narendra.sharma@gmail.com> wrote:
> Thanks Jonathan.
>
> Another related question is if I need to fetch only 1 row then what will be
> the difference between the performance of get_slice vs get_range_slices.
> The reason for this question is that we are using some code that uses
> get_range_slices. We have option of forcing it to use count=1 with
> get_range_slices or change the code to use get_slice.
>
> What would you recommend? What will be the net gain on the Cassandra side in
> computing the result?
>
> Thanks,
> Naren
>
> On Thu, Oct 14, 2010 at 11:12 AM, Jonathan Ellis <jbellis@gmail.com> wrote:
>>
>> get_range_slices never does "searching."
>>
>> the performance of those two predicates is equivalent, assuming a row
>> "start key" actually exists.
>>
>> On Thu, Oct 14, 2010 at 1:09 PM, Narendra Sharma
>> <narendra.sharma@gmail.com> wrote:
>> > Hi,
>> >
>> > I am using Cassandra 0.6.5. Our application uses the get_range_slices to
>> > get
>> > rows in the given range.
>> >
>> > Could someone please explain how get_range_slices works internally esp
>> > when
>> > a count parameter (value = 1) is also specified in the SlicePredicate?
>> > Does
>> > Cassandra first search all in the given range and then return top 1 or
>> > it
>> > some how reads only 1 and return them?
>> > What is the performance & I/O impact if we pass "start key" = "end key"
>> > in
>> > the SlicePredicate? Will it perform better than passing a range as
>> > ["Start
>> > key",""] with count = 1?
>> >
>> > Thanks,
>> > Naren
>> >
>>
>>
>>
>> --
>> Jonathan Ellis
>> Project Chair, Apache Cassandra
>> co-founder of Riptano, the source for professional Cassandra support
>> http://riptano.com
>
>



-- 
Jonathan Ellis
Project Chair, Apache Cassandra
co-founder of Riptano, the source for professional Cassandra support
http://riptano.com

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