Can you clarify what you mean by 'random between nodes' ?
On Wed, Jun 2, 2010 at 8:15 AM, David Boxenhorn <da...@lookin2.com> wrote: > I see. But we could make this work if the random partitioner was random only > between nodes, but was still ordered within each node. (Or if there were > another partitioner that did this.) That way we could get everything we need > from each node separately. The results would not be ordered, but they would > be correct. > > On Wed, Jun 2, 2010 at 4:09 PM, Sylvain Lebresne <sylv...@yakaz.com> wrote: >> >> > So why do the "start" and "finish" range parameters exist? >> >> Because especially if you want to iterate over all your key (which as >> stated by Ben above >> is the only meaningful way to use get_range_slices() with the random >> partitionner), you'll >> want to paginate that. And that's where the 'start' and 'finish' are >> useful (to be fair, >> the 'finish' part is not so useful in practice with the random >> partitioner). >> >> -- >> Sylvain >> >> > >> > On Wed, Jun 2, 2010 at 3:53 PM, Ben Browning <ben...@gmail.com> wrote: >> >> >> >> Martin, >> >> >> >> On Wed, Jun 2, 2010 at 8:34 AM, Dr. Martin Grabmüller >> >> <martin.grabmuel...@eleven.de> wrote: >> >> > I think you can specify an end key, but it should be a key which does >> >> > exist >> >> > in your column family. >> >> >> >> >> >> Logically, it doesn't make sense to ever specify an end key with >> >> random partitioner. If you specified a start key of "aaa" and and end >> >> key of "aac" you might get back as results "aaa", "zfc", "hik", etc. >> >> And, even if you have a key of "aab" it might not show up. Key ranges >> >> only make sense with order-preserving partitioner. The only time to >> >> ever use a key range with random partitioner is when you want to >> >> iterate over all keys in the CF. >> >> >> >> Ben >> >> >> >> >> >> > But maybe I'm off the track here and someone else here knows more >> >> > about >> >> > this >> >> > key range stuff. >> >> > >> >> > Martin >> >> > >> >> > ________________________________ >> >> > From: David Boxenhorn [mailto:da...@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 Grabmüller >> >> > <martin.grabmuel...@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:da...@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 <da...@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 <tcu...@vafer.org> >> >> >>> wrote: >> >> >>>> >> >> >>>> Sounds like you are not using an order preserving partitioner? >> >> >>>> >> >> >>>> On Wed, Jun 2, 2010 at 13:48, David Boxenhorn <da...@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."? >> >> >>> >> >> >> >> >> > >> >> > >> > >> > > >
