Straws in the Wind Blog Articles
I gave a talk last year entitled Automated Layer Management – Experiences At Mid Coast Water which was about mapping the area that would be affected by a mains pipe bursting in either a sewer or water network. (Yes it was a not very exciting title.) The mapping was all done in 2D as Oracle 10gR2 and before does not have any 3D capabilities that would help do the work in 3D.
The work also had many other aspects, the main one being that because the problem was clearly defined, described and attributed (eg invert levels below surface level), the solution could be fully automated via the use of very efficient trigger based processing.
The customer asked me to look at whether it would be possible to redo the solution such that it fitted seamlessly into the same framework as the current solution, but extend it to model the area that would be affected in 3D.
This involves modelling the pipe burst as a 3D solid and then calculating the intersection between it and a 3D model of the ground surface.
Since my customer is on 10gR2 I had to design a solution based on the lack of internal support for 3D solids, triangulated irregular networks etc. Also, the customer wants me to “look forward” to what is in 11gR1 and R2 that may help when an upgrade of the database software occurs.
Well, I came up with a solution that will actually run on SQL Server 2008 and PostgreSQL/PostGIS as both support linear and polygonal data with Z and M values.
The solution was presented at the Australia Oracle User Group (AUSOUG) annual conference Melbourne 16 – 17 November 2009. The title of the paper was – yes another bad title – Extending a 2D Zone of Influence to 3D using Oracle 10g and 11g SDO_TIN. (I changed the name of the PDF to make the document more descriptive of its contents.)
If anyone would like me to implement this solution for them in Oracle, PostGIS or SQL Server 2008 please feel free to email me.