|
|
| (Není zobrazeno 15 mezilehlých verzí od stejného uživatele.) |
| Řádek 1: |
Řádek 1: |
| {{Upravit}} | | {{freegiswiki|PostGIS Topology}} |
| | |
| [http://trac.osgeo.org/postgis/wiki/UsersWikiPostgisTopology PostGIS Topology] je rozšíření pro [[PostGIS]] umožňující ''topologickou'' správu vektorových dat v prostředí PostGIS/[[PostgreSQL]].
| |
| | |
| Více přednášky [[153UZPD#Přednášky|Úvod do zpracování prostorových dat]].
| |
| | |
| == Příklad ==
| |
| | |
| Data z [[Cvičná databáze PostGIS|cvičné databáze]] <tt>pgis_student</tt>.
| |
| | |
| <source lang=sql>
| |
| CREATE SCHEMA my_schema;
| |
| SET search_path TO my_schema,public,topology,gis1;
| |
| </source>
| |
| | |
| === Feature table 'tm50_cr' ===
| |
| | |
| <source lang=sql>
| |
| CREATE TABLE tm50_cr AS SELECT DISTINCT k.ogc_fid,k.tm50,k.geom FROM kltm50 AS k JOIN obce AS o ON ST_Overlaps(k.geom, o.geom);
| |
| SELECT COUNT(*) FROM tm50_cr;
| |
| </source>
| |
| | |
| <pre>
| |
| count
| |
| -------
| |
| 289
| |
| (1 row)
| |
| </pre>
| |
| | |
| [[Image:tm50-qgis-sf.png|640px|thumb|center|Klad mapových listu TM50 (území ČR)]]
| |
| | |
| === Vytvoření topologického schématu 'tm50_cr' ===
| |
| | |
| * [http://postgis.org/documentation/manual-svn/CreateTopology.html CreateTopology()]
| |
| | |
| <source lang=sql>
| |
| SELECT topology.createtopology('tm50_cr', 2065, 1);
| |
| </source>
| |
| | |
| ''Argumenty:''
| |
| * 2065 (EPSG)
| |
| * 1 (přesnost v mapových jednotkách, tj. v tomto případě v metrech)
| |
| | |
| <source lang=sql>
| |
| SELECT * from topology.topology;
| |
| </source>
| |
| | |
| <pre>
| |
| id | name | srid | precision | hasz
| |
| ----+-----------+------+-----------+------
| |
| 1 | tm50_cr | 2065 | 1 | f
| |
| </pre>
| |
| | |
| \dt tm50_cr.
| |
| | |
| <pre>
| |
| List of relations
| |
| Schema | Name | Type | Owner
| |
| ---------+-----------+-------+---------
| |
| tm50_cr | edge_data | table | postgis
| |
| tm50_cr | face | table | postgis
| |
| tm50_cr | node | table | postgis
| |
| tm50_cr | relation | table | postgis
| |
| (4 rows)
| |
| </pre>
| |
| | |
| === Přidání atributu topologie do feature table ===
| |
| | |
| * [http://postgis.org/documentation/manual-svn/AddTopoGeometryColumn.html AddTopoGeometryColumn()]
| |
| | |
| <source lang=sql>
| |
| select topology.AddTopoGeometryColumn('tm50_cr', 'my_schema', 'tm50_cr', 'topo', 'POLYGON');
| |
| </source>
| |
| | |
| <source lang=sql>
| |
| SELECT * FROM topology.layer;
| |
| </source>
| |
| | |
| <pre>
| |
| topology_id | layer_id | schema_name | table_name | feature_column | feature_type | level | child_id
| |
| -------------+----------+-------------+------------+----------------+--------------+-------+----------
| |
| 1 | 1 | my_schema | tm50_cr | topo | 3 | 0 |
| |
| </pre>
| |
| | |
| ''Poznámka:'' <tt>feature_type</tt> '3' odpovídá 'face' (1 - node, 2 - edge).
| |
| | |
| === Sestavení topologie (Geometry → TopoGeometry) ===
| |
| | |
| * [http://postgis.org/documentation/manual-svn/toTopoGeom.html toTopoGeom()]
| |
| | |
| <source lang=sql>
| |
| UPDATE tm50_cr set topo = topology.toTopoGeom(geom, 'tm50_cr', 1);
| |
| SELECT tm50,topo from tm50_cr limit 3;
| |
| </source>
| |
| | |
| <pre>
| |
| tm50 | topo
| |
| -----------+------------
| |
| M-33-29-D | (10,1,1,3)
| |
| M-33-30-C | (10,1,2,3)
| |
| M-33-30-D | (10,1,3,3)
| |
| (3 rows)
| |
| </pre>
| |
| | |
| Počet uzlů:
| |
| | |
| <source lang=sql>
| |
| SELECT count(*) from tm50_cr.node;
| |
| </source>
| |
| <pre>
| |
| count
| |
| -------
| |
| 313
| |
| (1 row)
| |
| </pre>
| |
| | |
| Počet hran:
| |
| | |
| <source lang=sql>
| |
| SELECT count(*) from tm50_cr.edge_data;
| |
| </source>
| |
| <pre>
| |
| count
| |
| -------
| |
| 601
| |
| (1 row)
| |
| </pre>
| |
| | |
| Počet stěn:
| |
| | |
| <source lang=sql>
| |
| SELECT count(*) from tm50_cr.face;
| |
| </source>
| |
| <pre>
| |
| count
| |
| -------
| |
| 290
| |
| (1 row)
| |
| </pre>
| |
| | |
| == Externí odkazy ==
| |
| | |
| * [http://2010.foss4g.org/presentations/3555.pdf State of the art of FOSS4G for topology and network analysis]
| |
| * [http://www.postgis.org/documentation/manual-svn/Topology.html PostGIS 2.0 Topology section of manual]
| |
| * [http://cs.wikipedia.org/wiki/Topologie Topogie] {{bullet}} [http://cs.wikipedia.org/wiki/Sedm_most%C5%AF_m%C4%9Bsta_Kr%C3%A1lovce Sedm mostů města Královce] {{bullet}} [http://en.wikipedia.org/wiki/Geographic_information_system#Topological_modeling Topological modeling]
| |
| * [http://cs.wikipedia.org/wiki/Geografick%C3%BD_informa%C4%8Dn%C3%AD_syst%C3%A9m#Vektorov.C3.A9_modely Vektorové modely]
| |
| * [http://strk.keybit.net/projects/postgis/ strk's page about PostGIS]
| |
| * [http://strk.keybit.net/blog/2011/10/14/postgis-topology-iso-sqlmm-complete/ PostGIS topology ISO SQL/MM complete]
| |
| | |
| {{Databáze}}
| |
| {{GIS}}
| |
| {{GFOSS}}
| |
