Ravi Kothuri

Spatial Information Management

Location is an inherent part of business data: organizations maintain customer address lists, own property, ship goods from and to warehouses, manage transport flows among their workforce, and perform many other activities. A majority of these activities entail managing locations of different types of entities, including customers, property, goods, and employees. Those locations need not be static—in fact, they may continually change over time. For instance, goods are manufactured, packaged, and channeled to warehouses and retail/customer destinations. They may have different locations at various stages of the distribution network.

A Sample Application

Throughout this book, you have learned many techniques relating to spatial technology: how to location-enable an application, how to perform spatial analysis, and how to view the results using dynamically generated maps.

Tips, Common Mistakes, and Common Errors

This is the last chapter of the book. Now that you have studied many techniques for how to location-enable your application and how to incorporate spatial analysis and visualization tools in your application, we think it is time for a little advice.

Generating Maps Using MapViewer

So far, you have seen how to use spatial-based queries and how to manipulate spatial objects. However, one important aspect is still missing: visualization of spatial objects using maps. After all, location information is all about maps, and to paraphrase a common saying, a map is certainly worth a thousand words. In this chapter, you will see how to enable map-based visualization of spatial data in your applications using Oracle MapViewer.

Manipulating SDO_GEOMETRY in Application Programs

So far, you have seen how to define and load spatial objects using the SDO_GEOMETRY type. You have also seen how to read spatial objects from SQL using SQL*Plus. In this chapter, we look at how to manipulate SDO_GEOMETRY types in the PL/SQL and Java programming languages. We also briefly cover C and Pro*C.

Loading, Transporting, and Validating Spatial Data

In the previous chapter, we introduced a new data type called SDO_GEOMETRY to store spatial data. This data type can store a variety of spatial objects: points (including those obtained by geocoding address strings), line strings, polygons, or more complex shapes. Points primarily represent the locations of application-specific entities such as businesses, customers, or suppliers. Line strings and polygons, on the other hand, represent the boundaries of geographical entities such as roads, cities, or states. In CAD/CAM-type applications, line strings and polygons can represent different entities such as the layouts of buildings, printed circuit boards, or shapes of different parts of an automobile.

The SDO_GEOMETRY Data Type

In the previous chapter, we discussed how to location-enable application data and how to organize geographic data into multiple tables, each containing SDO_GEOMETRY columns. In this chapter, we focus on storing and modeling different types of location information using the SDO_GEOMETRY data type in Oracle. The SDO_GEOMETRY type can store a wide variety of spatial data, including the following: A point, which can be used to store the coordinate location of, for example, a customer site, a store location, a delivery address, and so on A line string, which can be used to store the location and shape of a road segment A polygon, which can be used to store city boundaries, business regions, and so on Complex geometries, such as multiple polygons, which can be used to store boundaries for states such as Texas, Hawaii, and California

Spatial Indexes and Operators

In previous chapters, we examined how to store location information in Oracle tables. We augmented existing tables, such as branches, customers, and competitors, with an SDO_GEOMETRY column to store locations of data objects. In this chapter, we describe how to use this spatial information to perform proximity analysis.

Overview of Oracle Spatial

In Chapter 1, we observed that spatial information can add value to a range of different applications. We examined the benefits of storing spatial information together with other data in the database.

Location-Enabling Your Applications

Consider a business application that stores information about its branches (or stores), customers, competitors, suppliers, and so on. If we location-enable such a business application, we can perform the following types of analysis: Spatial query and analysis: Identify the number of customers in different sales territories of a branch of this business or a competitor. Network/routing analysis: Compute the route between a branch and the nearest customer or the supplier. Visualization: Display the results of spatial query or network analysis on a map and integrate this map in other components of the business application.