A Spatial Database Technology Update with Dr.Ignacio Guerrero, Intergraph

By Joe Francica

Directions Magazine (DM): What improvements and functionality have been added to Oracle9i? What are the advantages to those thinking of upgrading?

Dr.Ignacio Guerrero (IG): The database like Oracle and SQL Server are driven by an IT industry that is much broader than our niche. And they do some things in the database from version to version that we can leverage by not doing much of anything.So, for example the ability to work with clusters, scalability improvements, performance, stability, security...things that are there for us.Now, the specific functionality that impacts us is really not a whole lot that we get.

On Oracle9i, there were a couple of significant things that we leveraged: the workspace manager for example is at the core of our transaction manager. The improvement of their globalization, XML, new Java machine, additional improvements in PL/SQL, database availability (one of those things like, upgrade with minimal downtime)...these are general things that we get by default.

DM: Did Oracle do anything with handling linear networks and implementing dynamic segmentation?
IG: I think that was already in Oracle8i and it was very basic and we have not really taken advantage of it.

DM: Is it because you don't need to take advantage of it due to the functionality that Intergraph products already have?
IG: Yes.And the same thing happened with their coordinate transformation system.Our coordinate transformation system is much richer than theirs. So, really for us to use the Oracle would be, for us, a step back.One thing that they did in 9i that was pretty significant from the business point of view was that they separated the locator technology from Spatial. The locator comes with the standard edition of Oracle; while full Spatial comes with the enterprise edition, so there is a big price differential there.The Oracle Locator contains the basic functionality that we use, so we can run very well with Oracle Locator, so that was very good for us.

DM: What kind of functionality is in Locator?
IG: The way I see it is that Locator was targeted at LBS.So, they included the basic geometry types, indexing and geocoding as well. We usually supply the higher end functionality ourselves

DM: Did Oracle include any additional spatial primitives other than the basic types?
IG: Yes, they added arcs, strings, circles.One of the other things they started doing with 9i was moving their indexing to R-Tree from Quad Tree.And one of the advantages is that the performance is similar and the R-Tree is much easier to tune and manage.The Quad Tree indexing wth multi-level tessilation was very hard to tune.And we had a lot of issues with customer due to the tuning.

DM: Does the R-Tree indexing help with handling larger databases?
IG: Yes, the R-Tree works very well, actually.

DM: Is it still the preferred database among your customers?
IG: We have seen a bit of emergence of DB2 and SQL (Server) but not very fast.Oracle still has a command of the market

DM: Is there anything you have to do if a customer selects DB2 over Oracle?
IG: We have a data server for both DB2 and SQL Server.In neither case do we use their "data cartridge." Now, normally in spatial access, you have two types of queries: Window queries - give me a all the features in this area (like features within a minimum bounding rectangle [MBR]); and queries that involve a spatial join, and those that involve two tables. Normally, for many applications, including the web, the "window" queries are sufficient.What we have found, a simple indexing using MBR works and that is the implementation we have done for SQL Server and DB2.So, in other words, we would support spatial filtering but we would not support spatial joins.

DM: How are the spatial elements being stored if you are not taking advantage the spatial cartridge? Is it a BLOB (Binary Large Object)?
IG: Yes, it is our own invention BLOB which is a similar scheme that we use in (Microsoft) Access.One of the things we found is that for a large number of customers, the spatial filter is what they need.

DM: So there has not been a huge migration of customer into using any of thes enterprise spatial data.What does it take for a customer to say that we are going to move everything to a spatial database? Is there a certain threshold for customer to use move into a full spatial database instead of keeping the data as a BLOB?
IG: We have lots of customers who can live with regular Oracle and not go to Oracle Enterprise.If you are talking about local governments who don't have lots of people doing online transactions, then Oracle standard is fine.I don't see a lot of the Oracle Spatial.I saw at some point a little bit of de-emphasis on Oracle's part because of their desire to go exploit the Location-based services market as a priority.

Now in 10i, they are introducing a topology sytem.

DM: So how does that affect GeoMedia?
IG: We don't quite know yet; we have been looking at that but, I think we could possibly take advantage of it.You know that it is fairly similar in concept to the system that Laser-Scan's got.Looks like there is going to be a little bit of collision there of the two approaches.

DM: Is the Radius Topology from Laser-Scan a middleware solution that sits between the database and the client?
IG: No, it's built in the database.It uses triggers.

DM: Is it just another table in the database?
IG: They have some other tables to encode the topology and what they do is have a set of triggers that intercept the update to modify, and fix all the metadata.So, I think it is going to very similar to what Oracle is going to do.

DM: And from what I have heard, I assume that Microsoft is not going to put any spatial functionality inside SQL Server, is that correct?
IG: That's correct, I have not heard anything and they have been looking at it for four or five years.

DM: And there seems to be some confusion in the IBM camp with regard to how to promote the differences between DB2 and the recently obtained Informix suite with the Spatial Datablades.Is there any closer association between IBM and Intergraph?
IG: We do talk to the spatial group.My understanding is that they intend to merge those technologies at some point but I have not heard the timeframe for them.You know, one of the things that we are a little concerned about making a huge investment to adopt it right now is that we're pretty sure they are going to change it.

Dr.Guerrero is Vice President of Intergraph's Mapping and Geospatial Solutions Division, Huntsville, Alabama.He can be reached at .(JavaScript must be enabled to view this email address).

Published Tuesday, January 14th, 2003

Written by Joe Francica

If you liked this article subscribe to our newsletter...stay informed on the latest geospatial technology

© 2016 Directions Media. All Rights Reserved.