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From David Boxenhorn <da...@lookin2.com>
Subject Re: Range search on keys not working?
Date Wed, 02 Jun 2010 12:29:52 GMT
In other words, I should check the values as I iterate, and stop iterating
when I get out of range?

I'll try that!

On Wed, Jun 2, 2010 at 3:15 PM, Dr. Martin Grabm├╝ller <
Martin.Grabmueller@eleven.de> wrote:

>  When not using OOP, you should not use something like 'CATEGORY/' as the
> end key.
> Use the empty string as the end key and limit the number of returned keys,
> as you did with
> the 'max' value.
>
> If I understand correctly, the end key is used to generate an end token by
> hashing it, and
> there is not the same correspondence between 'CATEGORY' and 'CATEGORY/' as
> for
> hash('CATEGORY') and hash('CATEGORY/').
>
> At least, this was the explanation I gave myself when I had the same
> problem.
>
> The solution is to iterate through the keys by always using the last key
> returned as the
> start key for the next call to get_range_slices, and the to drop the first
> element from
> the result.
>
> HTH,
>   Martin
>
>  ------------------------------
> *From:* David Boxenhorn [mailto:david@lookin2.com]
> *Sent:* Wednesday, June 02, 2010 2:01 PM
> *To:* user@cassandra.apache.org
> *Subject:* Re: Range search on keys not working?
>
>  The previous thread where we discussed this is called, "key is sorted?"
>
>
> On Wed, Jun 2, 2010 at 2:56 PM, David Boxenhorn <david@lookin2.com> wrote:
>
>> I'm not using OPP. But I was assured on earlier threads (I asked several
>> times to be sure) that it would work as stated below: the results would not
>> be ordered, but they would be correct.
>>
>> On Wed, Jun 2, 2010 at 2:51 PM, Torsten Curdt <tcurdt@vafer.org> wrote:
>>
>>> Sounds like you are not using an order preserving partitioner?
>>>
>>> On Wed, Jun 2, 2010 at 13:48, David Boxenhorn <david@lookin2.com> wrote:
>>> > Range search on keys is not working for me. I was assured in earlier
>>> threads
>>> > that range search would work, but the results would not be ordered.
>>> >
>>> > I'm trying to get all the rows that start with "CATEGORY."
>>> >
>>> > I'm doing:
>>> >
>>> > String start = "CATEGORY.";
>>> > .
>>> > .
>>> > .
>>> > keyspace.getSuperRangeSlice(columnParent, slicePredicate, start,
>>> > "CATEGORY/", max)
>>> > .
>>> > .
>>> > .
>>> >
>>> > in a loop, setting start to the last key each time - but I'm getting
>>> rows
>>> > that don't start with "CATEGORY."!!
>>> >
>>> > How do I get all rows that start with "CATEGORY."?
>>>
>>
>>
>

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