tx was looking at http://code.google.com/p/javageomodel/ too
2012/5/14 aaron morton <aa...@thelastpickle.com> > So it seems it's not a good idea, to use Cassandra like that? > > Right. It's basically a table scan. > > Here is some background on the approach simple geo took to using > Cassandra... > http://www.readwriteweb.com/cloud/2011/02/video-simplegeo-cassandra.php > > Also PostGis for Postgress seems popular http://postgis.refractions.net/ > > Hope that helps. > > > ----------------- > Aaron Morton > Freelance Developer > @aaronmorton > http://www.thelastpickle.com > > On 12/05/2012, at 4:23 AM, cyril auburtin wrote: > > I was thinking of a CF with many many rows with id, type, latitude and > longitude (indexed), and do geolocation queries: type=all and lat < 43 and > lat >42.9 and lon < 7.3 and lon > 7.2 > > where all rows have type=all > (at least try how Cassandra deals with that) > So it seems it's not a good idea, to use Cassandra like that? > > There's also the possibly to do in parallel, other CF, with latitude in > rows, that will be sorted, so an indexed query can give us the right > latidue range, and then just query with logitude < and > > > What do you think of that > > thanks > > 2012/5/11 Dave Brosius <dbros...@mebigfatguy.com> > >> Inequalities on secondary indices are always done in memory, so without >> at least one EQ on another secondary index you will be loading every row in >> the database, which with a massive database isn't a good idea. So by >> requiring at least one EQ on an index, you hopefully limit the set of rows >> that need to be read into memory to a manageable size. Although obviously >> you can still get into trouble with that as well. >> >> >> >> >> On 05/11/2012 09:39 AM, cyril auburtin wrote: >> >>> Sorry for askign that >>> but Why is it necessary to always have at least one EQ comparison >>> >>> [default@Keyspace1] get test where birth_year>1985; >>> No indexed columns present in index clause with operator EQ >>> >>> It oblige to have one dummy indexed column, to do this query >>> >>> [default@Keyspace1] get test where tag=sea and birth_year>1985; >>> ------------------- >>> RowKey: sam >>> => (column=birth_year, value=1988, timestamp=1336742346059000) >>> >>> >>> >> > >
