Articles

STDensify: Densify (m)LineString or (m)Polygon geometry objects

I have a densify function for my PL/SQL (Package and Object) code. A SQL Server Spatial version exists as follows: Description This function add vertices to an existing vertex-to-vertex described (m)linestring or (m)polygon sdo_geometry. New vertices are added in such a way as to maintain existing vertices, that is, no existing vertices are removed. DensificationRead More

STInsertN: Insert single vertex into a geometry

SQL Server Spatial, unlike spatial database type systems such as PostGIS, does not provide coordinate editing functions: STAddPoint STUpdatePoint STDeletePoint These functions are not a part of either the SQL or OGC standards. In fact neither provide an API for the SQL editing of geometry objects. If one wishes to do so, one must programRead More

STUpdateN: Update (replace) a single vertex within a geometry object.

SQL Server Spatial, unlike spatial database type systems such as PostGIS, does not provide coordinate editing functions: STAddPoint STUpdatePoint STDeletePoint These functions are not a part of either the SQL or OGC standards. In fact neither provide an API for the SQL editing of geometry objects. If one wishes to do so, one must programRead More

STUpdate: Replace all points equal to the supplied point with replacement point.

SQL Server Spatial, unlike spatial database type systems such as PostGIS, does not provide coordinate editing functions: STAddPoint STUpdatePoint STDeletePoint These functions are not a part of either the SQL or OGC standards. In fact neither provide an API for the SQL editing of geometry objects. If one wishes to do so, one must programRead More

STDeleteN: Delete single vertex from geometry

SQL Server Spatial, unlike spatial database type systems such as PostGIS, does not provide coordinate editing functions: STAddPoint STUpdatePoint STDeletePoint These functions are not a part of either the SQL or OGC standards. In fact neither provide an API for the SQL editing of geometry objects. If one wishes to do so, one must programRead More

STDelete: Deleting vertices in geometry objects

SQL Server Spatial, unlike spatial database type systems such as PostGIS, does not provide coordinate editing functions: STAddPoint STUpdatePoint STDeletePoint These functions are not a part of either the SQL or OGC standards. In fact neither provide an API for the SQL editing of geometry objects. If one wishes to do so, one must programRead More

Using Oracle’s ST_GEOMETRY type hierarchy with SDO_GEOMETRY: ST_PointN and ST_NumPoints

Oracle Spatial has, for many versions, made available an implementation of the OpenGIS SFS type hierarchy. Today I will show how to use this type hierarchy do extract points from an SDO_GEOMETRY. The first example extracts the first and last point from a linestring constructed from Well Known Text. The second example finds the firstRead More

Spatial Representation of a Communications Pit

This article is about applying spatial and host database processing to solving a specific, and real, customer requirement: to visualise a communications pit and its contents on a map as a concept called a “Butterfly”. The solution uses logical connectivity within the data model to create spatial objects on the fly from minimal hard geometryRead More