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From Dr. Martin Grabm├╝ller <>
Subject RE: Range search on keys not working?
Date Wed, 02 Jun 2010 12:15:48 GMT
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.


	From: David Boxenhorn [] 
	Sent: Wednesday, June 02, 2010 2:01 PM
	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 <> 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 <> wrote:

			Sounds like you are not using an order preserving partitioner?

			On Wed, Jun 2, 2010 at 13:48, David Boxenhorn <> 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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