STAsEWKT — Implements an method to create Extended Well Known Text (EWKT) strings from the input @p_geometry. Introduction/Description The Open Geospatial Consortium’s, Simple Features Specifications (SFS) 1.1 and 1.2, as well as the SQL/MM standard, define a Well Known Text (WKT) format for use in interchanging or processing geometry data. These specifications are 2D inRead More
STGeomFromEWKT — Function that implements an import method for Extended Well Known Text including EWKT with SRID, Z and M ordinates.. Introduction/Description The Open Geospatial Consortium’s, Simple Features Specifications (SFS) 1.1 and 1.2, as well as the SQL/MM standard, define a Well Known Text (WKT) format for use in interchanging or processing geometry data. TheseRead More
There was a recent discussion about renewing PostGIS’s OGC Certificates. The discussion was interesting as it goes to the heart of the value of certification in the light of the evolution of standards. The contribution to the discussion was mostly an observation about product value and market positioning. And the standards I had in mindRead More
In Part 1 were were introduced to the IUF data, its structure, and processing (for Locality elements). In Part 2 we will look at ways of reducing the data volume of the seed file, and look at issues when processing whole layers (LGA will be used instead of LOCALITY). In Part 3 we will lookRead More
Over the years I have made available functions that generate the tiles of a grid given user input. These have been made available in Oracle, PostGIS and SQL Server Spatial (geometry). Here are the type signatures of these functions: Oracle Object Oracle Package PostGIS SQL Server Geometry Requirement A customer has the requirement to generationRead More
Note This is an article I wrote some years back which I have ported to my new website. Introduction There are a large number of geospatial data storage, delivery and interchange formats around nowadays. Including (I limit this discussion to vector data formats only): Geography Markup Language (GML) Keyhole Markup Language GPS eXchange Format (GPX)Read More
Introduction This article is about importing Victorian Government’s Incremental Update File (IUF) XML data into SQL Server. The IUF XML is used to publish whole (complete) datasets (e.g. Local Government Areas) or deltas/changes. As will be seen, it encodes geometry objects in its own unique way, and thus is a good dataset to demonstrate theRead More
A colleague asked me the other day how he could move data from a table in an Oracle database with a geometry column to SQL server. Of course I thought of this as a straight forward data migration exercise using standard database tools, in this case SQL Developer and SQL Server Management Studio (SSMS), whereRead More
STMulti — Function that returns @p_geometry as a MULTI* geometry Function Specification Description In situations where a geometry column is constrained to hold only the multi version of a base geometry, storage of a single geometry eg LineString requires that geometry to be wrapped as a multi geometry eg MultiLineString. ALTER TABLE [dbo].[Colony] WITH CHECKRead More
STRound — Function which rounds the ordinates of the supplied geometry. Function Specification Description The result of many geoprocessing operations in any spatial type can be geometries whose ordinates (X, Y etc) have far more decimal digits of precision than the initial geometry. Additionally, some input GIS formats, such as shapefiles (which has no associatedRead More
