This article describes the elements of a telecommunications pit and shows how they can be spatially represented. In particular the concept of a butterfly as a method for displaying the walls of a pit is introduced.
ESRI hosts a set of community created, domain-specific, data models on its website. As I understand the licensing of these data models, they are effectively free and open source. I have converted some of these data models into a form that they can be used natively in any of the current spatially enables databases egRead More
Over on the Oracle Technology Spatial Forum this question was asked: I want to store duplicate geometry intentionally, will it have any problems ?? Because same data comes from different sources and going to be big database system. (The article is here ) Here is my answer repackaged for this blog. The questioner’s question canRead More
As a spatial practitioner familiar with many aspects of spatial data capture and processing, I have been watching the responses to the opportunity that the National Broadband Network (NBN) offers the people of Australia and its federal, state, local and private spatial practitioners. One hears very little from NBN Co about what it is doingRead More
A question was asked on the Oracle Technology Network Spatial forum: I am trying to select sdo_gtype from all tables in schema, i mean to execute same sql statement given below for entire schema. Any help on the usage of dynamic sql in PLSQL to execute select statement for all tables in the schema. HereRead More
Disclaimer What follows is a personal opinion based on experience. While many statements appear critical of the people who create and administer spatial metadata in Australia and overseas that is not my intention: we all do what we can do given time, staff constraints and education and training background. Some assertions may appear to beRead More
This article was written before TypeMod was introduced eg Geometry(Polygon,28355) As I have pointed out in other blog articles, spatial data quality should not engender either/or solutions when building business applications. That is, if I can only create points for parcel centroids that fall within land parcels, then I don’t just build the rule inRead More
There has been some discussion over on the PostGIS email list about the use of primary keys on tables by GIS client software such as uDig, QGis, MapInfo etc. It is a discussion that comes up now and again (perennial, I suppose) especially when new users of PostGIS (or Oracle on the Oracle forum etc)Read More
In my consulting travels I, like many other database-loving specialists, find databases with little (a Primary Key, perhaps) or no constraints being applied to the data model managed by a relational database (which may be Oracle, SQL Server, PostgreSQL, MySQL etc). I finalised a report for a Government Department here in Australia recently where thisRead More