Spatial Database Engines help manage spatial data to provide a quicker retrieval of that data from database engines such as Oracle, SQLSever and Informix.
ArcSDE is ESRI’s gateway between ArcGIS software and IBM DB2, Informix, Microsoft SQL Server, and Oracle RDBMS.
MapInfo GIS Extension
MapInfo’s spatial data cartridge allowing the addition of spatial functions to Oracle8i Spatial.
Oracle Spatial is the spatial cartridge that works with Oracle9i to provide spatial object type storage, indexing, and operations, to support a variety of location-based services (LBS) and 3rd party GIS solutions.
Radius Topology enhances Oracle Spatial to provide improvements to speed and consistency of spatial data handling. WinQuery
WinQuery offers a way of linking any corporate relational database to WinGIS 2000. Connects WinGIS to multi-user databases like SqlServer, Oracle, SQLBase, Sybase, Interbase, MySQL… to provide an enterprise-wide GIS solution.