The Erdős unit distance problem asks how many pairs of points can sit exactly one unit apart. Paul Erdős guessed the answer in 1946, and the guess stood for eighty years. In May 2026, an OpenAI model found a counterexample. I checked the grid trick behind it in SQL Server, spatial queries included.
SQL SERVER – Beginning SQL 2012 – Spatial Unions and Collections
Aggregates are not just for sales totals. Much like a jigsaw puzzle, spatial unions assemble land coordinates together. Learn spatial unions and collections in SQL 2012.
SQL SERVER – Validating Spatial Object as NULL using IsNULL
How do spatial functions handle NULL? I show two ways of validating a spatial object as NULL: the IsNULL method, which returns 0 or NULL, and IsValidDetailed.
SQL SERVER – Validating Spatial Object with IsValidDetailed Function
Invalid spatial objects used to give only a simple error. The IsValidDetailed function tells you whether a shape is valid and, when it is not, the reason why.
SQL SERVER – Finding Shortest Distance between Two Shapes using Spatial Data Classes – Ramsetu or Adam’s Bridge
Using ShortestLineTo in SQL Server spatial data classes, I find the shortest distance between two shapes, with a fun Ramsetu, or Adam’s Bridge, example.
Finding the Nearest Location With a Spatial Index
A nearest location query in SQL Server needs TOP, STDistance in WHERE and ORDER BY, matching SRIDs, and a checked spatial plan.
Spatial Indexes: Speeding Up Distance Searches
Use spatial indexes for geography distance searches, compare actual plans and reads, and inspect tessellation with built-in diagnostics.