If you doing geo stuff you may want to take a look at the geo extension for couch db http://github.com/vmx/couchdb
Sounds like it may give you many if the features your thinking about out of the box. Aaron On 20 Aug 2010, at 20:54, Jone Lura <jone.l...@ecc.no> wrote: > Thank you for your effort. > > Im pretty sure I will make it work. > > Have a nice weekend! > > On 20/08/2010 10:48, Thorvaldsson Justus wrote: >> >> If you only want to check the last 5 min, make time a part of your key >> And make a customized sort and sort by the time. Remember sort is made when >> inserting data. http://www.sodeso.nl/?p=421 >> Or make a range check that understands the time limit, should work I think >> from the top of my head. >> >> But you don’t want a lot of small rows and also not to fat rows so.. >> Perhaps there is some time limit that could be rowed >> And sc is long&lat and you can figure a way to make a range check on one of >> them if they arnt to many perhaps It would work. >> /J >> There are so many opportunities to model that you probably want to make >> several and test them >> >> Från: Jone Lura [mailto:jone.l...@ecc.no] >> Skickat: den 20 augusti 2010 10:37 >> Till: user@cassandra.apache.org >> Ämne: Re: SV: SV: Help with getting Key range with some column limitations >> >> Thanks! Read your blog a few times, but it's hard to get rid of sql thinking. >> >> So if I create a new standard ColumnFamily with a rowId and geohash a >> lat/lon into a UTF8Type, I could geohash the boundingbox, and query for all >> matching columns. Or do I always need to know the rowId to do a slicerange? >> I also need to only get the columns that are modified within last 5 minutes. >> >> Jone >> >> >> On 20/08/2010 10:05, Thorvaldsson Justus wrote: >> I think you should try to do it some other way than iterate, it sounds super >> suboptimal to me. Also the plugin option he was thinking of I think is >> changing Cassandra sourcecode, kind of hard when Cassandra is changing so >> fast but very possible. I think you should look at >> http://blip.tv/file/4015273 and perhaps my blog post about the same thing at >> www.Justus.st Cassandra post 4 more on Data model >> >> Exampel code in java, start and end key, next iteration the end should be >> the last key that you collected, depends how you made you model >> //Keyrange is for what row key, you can specify what row startkey,endkey and >> how many rows >> KeyRange keyRange = new KeyRange(700); >> keyRange.setStart_key(rowId); >> keyRange.setEnd_key(rowId); >> >> //Specify what supercolumns you want to get >> SliceRange sliceRange = new SliceRange(); >> sliceRange.setStart(new byte[] {}); >> sliceRange.setFinish(new byte[] {}); >> >> /J >> >> Från: Jone Lura [mailto:jone.l...@ecc.no] >> Skickat: den 20 augusti 2010 08:53 >> Till: user@cassandra.apache.org >> Ämne: Re: SV: Help with getting Key range with some column limitations >> >> Thanks for you suggestions. >> >> I tried to iterate them, however I could not get it to work (pretty sure its >> my code). Im still not to familiar with Cassandra, so could you provide a >> small example? >> >> The key count could be up to atleast 20k and maybe more, and users should >> not wait for more than 10 seconds for their map, so I also want to >> investigate the plugin suggestion. Does the plugin exist? or do I have to >> develop it myself? Are there any documentation on plugin development for >> Cassandra? >> >> Best regards >> >> Jone >> >> >> On 19/08/2010 08:42, Thorvaldsson Justus wrote: >> You should iterate through them, get 200 then go get the next 200 and so on. >> Also if checking a bounding box to another.. perhaps try sorting them so you >> could start looking at both ends, perhaps make the iteration smaller until >> match somehow? >> Just my simple coins, also upgrading will probably be needed to iterate >> through RP because of bugs. But that should be simple enough to 6.4 >> /Justus >> >> Från: Jone Lura [mailto:jone.l...@ecc.no] >> Skickat: den 18 augusti 2010 20:32 >> Till: user@cassandra.apache.org >> Ämne: Help with getting Key range with some column limitations >> >> Hi, >> >> We are trying to implement Cassandra to replace one of our biggest SQL >> tables, and so far we got it working. >> >> However, for testing I'm using Cassandra 0.6.2, Java and Pelops. (Pelops not >> that important for my question) and need suggestions on how to solve a >> problem retrieving a key range based on the following. >> >> <Keyspace Name="AIS"> >> >> >> >> >> ColumnType="Super" >> CompareWith="LongType" >> KeysCached="100%" >> CompareSubcolumnsWith="UTF8Type" /> >> ... >> </Keyspace> >> >> The super column got columns for longitude and latitude. >> >> 1. Need to get get max long number for key >> 2. The key should also have supercolumns latitude and longitude column >> intersecting (inside) with a given boundingbox. >> >> Currently I'm doing like this >> >> >> KeyRange keyRange = new KeyRange(); >> keyRange.setStart_key(""); >> keyRange.setEnd_key(""); >> keyRange.setCount(700); >> >> And checking every row in db if it match my bounding box. >> >> But there are a lot more than 700 keys.. and if i set a higher count, the >> get_range_slice get a Timeout Exception. >> >> Any ideas? >> >> Best Regards >> Jone >> >> >
