[OSGeo-Discuss] Image Management in an RDBMS...(was OS Spatialenvironment 'sizing')

[Ed McNierney]

Well, I'm just one opinion, but I USED to store 17 million rasters in a database, and got tired of the hassles, so I switched to a file-based storage system.  I try to manage lots of tiles of imagery over the United States and Canada, with multiple pyramid layers and constant revision of imagery, and it's not that big a deal.  It's been a very part-time job for one guy for several years now.

It's very helpful to store the metadata in a database (PostgreSQL/PostGIS) but I don't see the benefit of storing the raster data there, too - and I don't like having the mechanics of my raster access be a mystery to me.  I like to know where exactly the data is and how it's accessed.

     - Ed

Ed McNierney
Chief Mapmaker
Demand Media / TopoZone.com
73 Princeton Street, Suite 305
North Chelmsford, MA  01863
Phone: 978-251-4242, Fax: 978-251-1396
ed at topozone.com

-----Original Message-----
From: discuss-bounces at lists.osgeo.org [mailto:discuss-bounces at lists.osgeo.org] On Behalf Of Chris Holmes
Sent: Wednesday, February 20, 2008 7:46 PM
To: OSGeo Discussions
Subject: Re: [OSGeo-Discuss] Image Management in an RDBMS...(was OS Spatialenvironment 'sizing')


> - When you consider the complexities that Google must be facing with 
> GE in trying to manage 256x256k tiles of imagery over the entire 
> world, at multiple pyramid layers and with constant revision of 
> imagery, you can soon see that a file based approach would lead to a major headache.

He he, I think I'd write that same sentence but substitute 'database approach' for 'file based approach'.  I'd be pretty shocked if Google were using any kind of database for their tiles.  They certainly aren't paying oracle or arcsde license fees.  They could have a custom mysql solution, but I'd guess it's all on the Google File System: 
http://labs.google.com/papers/gfs.html

Also, I think it's still in pretty beta development, but Geomatys has been working on PostGRID - http://seagis.sourceforge.net/postgrid/index.html and
http://www.foss4g2007.org/presentations/view.php?abstract_id=225 have some information.  I believe is pretty attached to java, but I think does some of what you want, managing the metadata in the database. 
Though I could be wrong about if it's close to what you're thinking of, my understanding of the raster side of the fence has never been that strong.

best regards,

Chris