The following is a “general” information about Oracle Spatial to give the reader a brief overview, and links to useful reading resources:

1. the difference between Oracle Locator and Oracle Spatial:

Oracle Locator: a feature of Oracle Database (Standard and Enterprise Editions), provides core location functionality needed by most customer applications and partner solutions. (Locator is not a solution for complex GIS applications .)  Developers can extend existing Oracle-based applications, since with Locator they can easily incorporate location information directly in their applications and services. This is possible because location data is fully integrated in the Oracle server itself. Geographic and location data are manipulated using the same semantics applied to the CHAR, DATE or INTEGER types that are familiar to all users of SQL.

Oracle Spatial: an option to Oracle Database Enterprise Edition, augments Locator, and provides a robust foundation for complex GIS applications which require more spatial analysis and processing in Oracle Database. It includes spatial functions (including area, buffer, centroid calculations), advanced coordinate systems support, linear referencing system, and aggregate functions. Significant new capabilities in this release address the challenging business-critical requirements from the public sector, defense, logistics, energy exploration, and business geographics domains.

2. to check if oracle spatial component is “installed” and “valid” in your database use the following query: SELECT COMP_NAME,VERSION,STATUS FROM DBA_REGISTRY;

3. when you have spatial data stored in your database, you can view it using “Oracle Fusion Middleware MapViewer“:http://www.oracle.com/technetwork/middleware/mapviewer/overview/index.html

OR

you can integrate your Oracle Spatial data with ESRI ArcGIS software and view the data in their ArcGIS Desktop , this requires registering the oracle spatial data with ArcGIS Geodatabase, this paper is very good paper to read: http://download.oracle.com/otndocs/products/spatial/pdf/spatial_wp09_bestprac.pdf