IOUG Spatial Summit 2016 Assembling a large scale map for the Netherlands Speaker : Date : E-mail : Richard Huesken January 28 th, 2016 richard.huesken@transfer-solutions.com WWW.TRANSFER-SOLUTIONS.COM
BRAVO Transfer-Solutions OVERVIEW Customer : SVB-BGT The organization that is responsible for assembling a large scale map database for the Netherlands CHALLENGES / OPPORTUNITIES Establish a countrywide topology of skin of the earth objects Automated data assembly Assemble geographic data from > 450 sources 100M Objects Use of circular arcs SOLUTIONS Oracle Database 12c Enterprise Edition Spatial and Graph Option Spatial Vector Acceleration enabled Partitioning RESULTS - Single dataset for large scale map data Usage 1:500 1:5000 Countrywide Collect data once, use many times Topologically correct dataset Automated data assembly with minimal user effort.
3 Introduction
4 Introduction Transfer Solutions Oracle Gold Partner Largest independent Oracle partner in the Netherlands Focus on Oracle and Java technology Consulting Managed services Education
5 Assembling a large scale map Large scale map data Scale 1:500 1:5000 Business case Requirements Solution Results Recommendations
6 Business Case Current problems Collected by different organizations Separate datasets Different storage formats Different object types Different definitions Data has been collected at different points in time Data is collected with different quality standards
7 Business Case Separate datasets
8 Business Case Separate datasets
9 Business Case BGT Objectives Single dataset, 2D, countrywide Shared data Collected once, used many times Uniform definition of objects Requirements Automated data assembly Topologically correct
10 Business Case BGT Country wide Area : 41,453 km 2 (currently: 5,213 km 2 ) Land : 33,893 km 2 Water : 7,650 km 2 BGT estimates 100,000,000 objects Source data providers 450 organizations Implementation Required by Law
11 Business Case BGT Process 1.Source data providers Towns Counties MoT MoD 5.Users Provide feedback 4.PDOK Geo Data Distribution Portal 2.SVB-BGT Assemble 2 data, Serialize changes 3.Cadastre Keep registration, History of changes
12 BGT Automated Data Assembly
13 BGT Before Assembly
14 BGT After Automated Assembly
15 BGT After Automated Assembly
Requirements - BGT Specification GML 3.1.1 Simple features profile Extended with circular arcs (GM_ARC) Ordinates rounded to 3 decimals ( mm grid ) Topology Adjacent objects share coordinates Technical tolerance Minimum distance from point to a line. Set to 0.0005 m ( 1/2 mm)
17 Automated Assembly - Solution Phase 1: Geometric approach Eliminate gaps and overlaps Stroke arcs selectively Phase 2: Topological finish Locate missing vertices (nodes) Add missing nodes Replace arcs
18 Geometric approach mm grid Object B Low Quality Object A High Quality
19 mm grid sdo_difference Object B Low Quality Object A High Quality
20 mm grid align object B Object B Low Quality Object A High Quality
21 mm grid add collinear points to object A Object B Low Quality Object A High Quality
22 mm grid align both objects Object B Low Quality Object A High Quality
23 Spatial Vector Acceleration (SVA) New feature in 12c New code path for spatial operations Performance improvements SVA optimizes sdo_geometry Consecutive segments may be combined Order of segments is not maintained Collinear points are removed
24 Geometric approach - arcs
25 Arcs - overlap
26 Arcs middle points
27 Arcs stroke arcs selectively
28 Arcs final result
29 Automated Assembly - Solution Phase 1: Geometric approach Eliminate gaps and overlaps Stroke selected arcs Phase 2: Topological finish Locate missing vertices (nodes) Add missing vertices Replace arcs
30 Locate missing nodes
31 Missing nodes - example
32 Missing nodes - detail
33 Missing nodes add node (vertex)
34 Replace Arc example
35 Replace Arc detail
36 Replace Arc result
37 Results A topologically correct dataset Arcs are preserved wherever possible 99.99% Automatic resolution in the first run Datasets with exceptions are rejected. A few objects are adjusted manually The data is processed successfully in a second run.
38 Recommendations Technical Use Oracle Spatial & Graph 12c Use Spatial Vector Acceleration (SVA), with caution Use Partitioning Functional Circular arcs are complicated Use the simple features profile without arcs
Questions Answers CONSULTING MANAGED SERVICES EDUCATION WWW.TRANSFER-SOLUTIONS.COM WWW.TRANSFER-SOLUTIONS.COM 39