I'm looking at the geometry data type in Sql Server 2008 and it looks interesting but the documentation does not seem that good. Would I be able to store cones, cylinders and spheres in the WKT format? These features tr开发者_如何学Goaditionally have a radius and not hundreds of points.
To the best of my knowledge your are going to have to use an external application to render your shape as a large number of points. See this blog for a technique for rendering circles.
One possibility to consider is a CLR proc to render the shapes you need and a view with indexes. I don't know how well that will perform, but it just might work.
sorry for the late reply. You could always write your own User-Defined-Type called Circle, with two properties namely Centroid and Radius.
Inside the newly formed UDT, create a method that takes the properties Centroid (Point3D), and Radius (Double). After this, create a method that uses both SqlGeometry and SqlGeometryBuilder to build the newly formed object.
First, create a Point instance of Geometry. Inherit the Centroid values from the class object, then, create another Geometry Polygon that's derived from the Point object, and STBuffer(Radius) it.
Below is my example: (written in 30min)
public SqlGeometry ToSQLGeometry()
{
int srid = this.SRID; // i.e. 4326
SqlGeometry geom = new SqlGeometry();
SqlGeometryBuilder gb = new SqlGeometryBuilder();
OpenGisGeometryType pt = OpenGisGeometryType.Point;
gb.SetSrid(srid);
gb.BeginGeometry(pt);
gb.BeginFigure(this.Centroid.X, this.Centroid.Y, this.Centroid.Z, this.Centroid.M);
gb.EndFigure();
gb.EndGeometry();
geom = gb.ConstructedGeometry;
geom = geom.MakeValid(); // Optional for Point data
SqlGeometry geomCircle = new SqlGeometry();
geomCircle = geom.STBuffer(this.Radius);
return geomCircle;
}
When you've done this in VS2010 by using the CLR project type, you can deploy it to your database.
In SQL, you can call the object as such:: Parse(X Y Z M,R)
declare @c Circle
set @c = Circle::Parse('5 6 7 8,2')
select 'Circle', @c.ToString(), @c.ToSQLGeometry()
Had a quick look around and found this MSDN page on Spatial Samples. It covers all the Methods to enter data in WKT, WKB & XML(GML) as well as functions to view the in Human Readable form. It also covers MakeValid, STIsValid & STSrid.
There looks to be a fair few SQL examples that you may find useful
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