Jim Gray, Alex Szalay, and Gyorgy Fekete
This article explains how to add spatial search functions (point-near-point and point in polygon) to Microsoft SQL Server™ 2005 using C# and table-valued functions. It is possible to use this library to add spatial search to your application without writing any special code. The library implements the public-domain C# Hierarchical Triangular Mesh (HTM) algorithms from Johns Hopkins University. That C# library is connected to SQL Server 2005 via a set of scalar-valued and table-valued functions. These functions act as a spatial index.