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Converting Mappoint routes to SqlGeography

The mapping services from microsoft aren't limited displaying maps in Virtual Earth, and not only limited to websites. There are numerous webservices for, resolving locations to longtiudes and latitudes as well as a routing api. I am working on something for SQLBits to enable people to lift share...

Posted to Simons SQL Blog (Weblog) by simonsabin on Sun, Feb 22 2009
SQL Server 2008 Spatial - How to create a circle?

How do you create a circle in a planar system. Ok so there are some funky algorithms for creating a set of points all the way round the circle. Well there is a much easier way. Create a point i.e. POINT (10 10) and the use the STBuffer(radius) method to get a circle whose centre is at the point and with...

Posted to Simons SQL Blog (Weblog) by simonsabin on Wed, Jan 9 2008
SQL Server 2008 Spatial - Performance of database calls follow up

I recently blogged about the performance of passing spatial data to the database.( SQL Server 2008 Spatial - Performance of database calls? ) In it I found that the the performance radically dropped off as the number of points increases. Whilst this was suprising I had used my usual approach of eliminaing...

Posted to Simons SQL Blog (Weblog) by simonsabin on Tue, Jan 8 2008
SQL Server 2008 Spatial - Performance of database calls?

There are 4 ways of holding spatial data, Well Known Text (WKT), Well Known Binary (WKB), Geography Markup Language and the base spatial type (SqlGeometry or SqlGeometry). This leads me on to the question how should you pass the data to SQL Server. I've heard bad things about passing udts and so...

Posted to Simons SQL Blog (Weblog) by simonsabin on Mon, Jan 7 2008
SQL Server 2008 Spatial - Which is faster WKT or WKB?

I've just posted two methods for creating geometries in client code. The examples use Stylus points from an ink canvas but any collection of points will go. After doing that I ran some tests to compare the two. I found that in generally the WKB method was ~70% faster to build the WKB and 40% faster...

Posted to Simons SQL Blog (Weblog) by simonsabin on Fri, Jan 4 2008
SQL Server 2008 Spatial - Converting from Ink Strokes to geometries

The following snippet will convert an strok collected using an Ink Canvas in WPF to a LINSTRING geometry. The first uses the Well Known Text format WKT. //Text representation of a line is LINESTRING (x1 y1,x2 y2 x3 y3....) //create an string array to store the points string [] pnts = new string [e.Stroke...

Posted to Simons SQL Blog (Weblog) by simonsabin on Fri, Jan 4 2008
SQL Server 2008 Spatial - Using it in .Net code

So you want to use the SqlGeometry and SqlGeogrpahy collections in .Net. I found the lack of friendly collection based properties and methods suprising, i.e. no iterators, no collections which you can add to.( http://sqlblogcasts.com/blogs/simons/archive/2007/12/09/Katmai-Spatial---First-thoughts.aspx...

Posted to Simons SQL Blog (Weblog) by simonsabin on Mon, Dec 31 2007
Katmai Spatial - What's a geometry

Following on my previous post on discovering the spatial types I mention that one of the aspects to understand is the different types of geometries. Point Fairly this is obvious its a single spot that has an X and a Y co-ordinate. Multi Point A group of points that are not connected. (if they were connected...

Posted to Simons SQL Blog (Weblog) by simonsabin on Sun, Dec 9 2007
Katmai Spatial - First thoughts

I've been doing some work with the Spatial types in Katmai and these are my first thoughts. The first thing is that the data type is the same used by SQL as used in your .Net code. So what does that mean, · You use the same methods, which is great from a familiarity perspective · When calling the...

Posted to Simons SQL Blog (Weblog) by simonsabin on Sun, Dec 9 2007

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