I want to apologize even before I begin because there’s so much information that I feel I need to share with others that my topics may jump around.
Notice how I didn’t say “The world of Oracle Spatial”? That’s because there is an alternative in the land of GIS (Geographic, Information, System), you don’t have to use Oracle’s spatial module. The big dog in GIS is ESRI and if you use ArcSDE (component of ESRI) it has its own way of doing spatial stuff. Before I get down and dirty with the technical aspects of running and maintaining a spatial database, I feel that it’s important that you (the reader) know upfront you do have a choice of how you can mange your spatial storage.
*Steps up on soapbox*
The ESRI company started out as bunch of engineers who wanted to develop geographic software. The thought was great but, engineers have this idiosyncrasy about delegating work, they think they can do it all and it reflects grossly in their product. The first thing you will become distinctly aware of is that Oracle is kind of an afterthought in the eyes of ESRI, SQL Server is all that is holy with ESRI and the reason for that is because most of it’s customers run SQL Server. Why anyone would want to run an enterprise system with terabytes of data on SQL Server is beyond me (yes, I am Oracle biased). The second thing is Bind variables, they are unheard of, if you have a spatial database and you run ESRI get use to thousands of literal statements plaguing your shared pool . I have done battle for two years with these people and they just don’t get it. There are days where I really want to hop on an airplane, fly to CA and cause bodily harm to the development staff. End of rant.
*Steps off soapbox*
As far as using Oracle spatial vs ESRI “spatial” there are pros and cons of each, it’s up to you to decide which is best for your environment and skill set. I look at using Oracle spatial as kind of like “more moving parts”. The less “stuff” I have to deal with in a database the better, especially if it’s big. I figure if I let ESRI handle ESRI there’s less that can go wrong. I hang out over on ESRI’s forums and the number of Oracle Spatial problems are limited but when there are, they’re usually pretty bad and the question(s) go unanswered. As far as performance gained with Oracle spatial, the jury is still out on that one with me because I’m waiting to see what ESRI’s new release of 9.2 is going to be like. Apparently, they’re going to finally take advantage of the SDO_GEORASTER parameter. Right now they’re only using the SDO_GEOMETRY parameter which handles shape files. It’s like they developed a product, packaged it up, shipped it out, and forgot to put the CD’s in the box. Yeah, if you do use Oracle spatial (now) you get rid of your F and S tables but what’s the sense if you can only use half of the modules ability? It boils down to if you want to use Oracle Spatial when ArcSDE 9.2 comes out you’re going to have to completely drop your rasters and bring them back in (at least that’s the way I see it). I can see it now, managers across the nation giving birth to small farm animals when they find out they’re going to have to drop terabytes of data to take full advantage of Oracle Spatial because of ESRI laziness.
The last thing I want to do is go over anyone’s head when I’m on a roll talking about this stuff so if I mention something that you don’t quite get or want me to elaborate on, please speak up and I’ll be more than happy to pull the reins in sit for a spell.