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From Dr. Martin Grabm├╝ller <Martin.Grabmuel...@eleven.de>
Subject RE: Range search on keys not working?
Date Wed, 02 Jun 2010 12:34:24 GMT
I think you can specify an end key, but it should be a key which does exist in your column
family.
 
But maybe I'm off the track here and someone else here knows more about this key range stuff.
 
Martin


________________________________

	From: David Boxenhorn [mailto:david@lookin2.com] 
	Sent: Wednesday, June 02, 2010 2:30 PM
	To: user@cassandra.apache.org
	Subject: Re: Range search on keys not working?
	
	
	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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