All, thanks for your quick responses! Quad tiles look like a smart way to create an index. So to lookup a single point or a quad tile, this is fine. But for my application I need another lookup - by bounding box with any ratio and size. Is there a way to look up a special bounding box with this index? I think this will be a little more complicated without conventional multi-column indices. Hmm, I think you could take a maximum number of quad lookups which contain the requested box, what do you think?
My current optimization includes: - using mediumint for lat/lon - enough for ~2 meters resolution - using a bounding box first for point+radius calculation and then selecting the circle with a Pythagoras approximation, which is exact enough For the first, I want to use MySQL. If you are interested in some benchmark data, I can post ... > Instead of indexing by precise coordinates you could index by virtual > tiles as it is done in OSM's main DB since a year ago with nice > performance boost: > > http://wiki.openstreetmap.org/index.php/QuadTiles > > good luck, > Stefan > > > On Thu, Sep 11, 2008 at 1:49 PM, Andreas Kalsch <[EMAIL PROTECTED]> > wrote: > > Hey, > > > > last week I made some experiments with huge datasets of lat/lon points. > I use MySQL 5.0, which partially support GIS extensions, including R-trees. > But it is still not able to make queries based on the GIS features, so I > have to use the normal way - multi-column indexes on lat/lon columns. It > works well but probably there is a way to make it even quicker ;) > > > > Has anybody used GIS successfully in MySQL or PGSQL and can tell me how > the performance compares between the two techniques? > > > > Thanks, > > > > Andi > > -- > > Psssst! Schon das coole Video vom GMX MultiMessenger gesehen? > > Der Eine für Alle: http://www.gmx.net/de/go/messenger03 > > > > _______________________________________________ > > dev mailing list > > [email protected] > > http://lists.openstreetmap.org/listinfo/dev > > -- Psssst! Schon vom neuen GMX MultiMessenger gehört? Der kann`s mit allen: http://www.gmx.net/de/go/multimessenger _______________________________________________ dev mailing list [email protected] http://lists.openstreetmap.org/listinfo/dev
