In the previous post, we finished by calculating population density for the city of Chicago. Today we will continue to build on that same dataset and will look at a cool way to visualize our spatial data using SSRS in SQL Server 2008 R2. If you haven’t done so yet, run through the tutorials in posts oneand two to bring your database up to speed. First of all, let’s look at an interesting way to join spatial datasets, as well as building a little on the knowledge from the last post about geography vs. geometry data. If you remember my comments about spatial reference systems, you’ll remember that the only way to truly measure distance is to use the geography type, which maps to three-dimensional space. However, you’ll also remember that the geography type supports far less functions that the geometry type. One of the convenient, and missing, functions from the geometry type is STCentroid() which returns a point at the center of mass of any shape. There’s a good explanation here. Read More
