PostGIS Topology - Revision history

⚠️Strk: /* External links */ keybit.net -> kbt.io

2017-11-06T21:55:53Z

External links: keybit.net -> kbt.io

← Older revision		Revision as of 21:55, 6 November 2017
Line 329:		Line 329:
	* PostGIS Topology [http://trac.osgeo.org/postgis/wiki/UsersWikiPostgisTopology wiki page]		* PostGIS Topology [http://trac.osgeo.org/postgis/wiki/UsersWikiPostgisTopology wiki page]
	* [http://2010.foss4g.org/presentations/3555.pdf State of the art of FOSS4G for topology and network analysis] (FOSS4G 2010)		* [http://2010.foss4g.org/presentations/3555.pdf State of the art of FOSS4G for topology and network analysis] (FOSS4G 2010)
	* [http://strk.~~keybit~~.~~net~~/projects/postgis/ strk's page about PostGIS]		* [http://strk.kbt.io/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] (strk's blog)		* [http://strk.kbt.io/blog/2011/10/14/postgis-topology-iso-sqlmm-complete/ PostGIS topology ISO SQL/MM complete] (strk's blog)
	* [http://strk.~~keybit~~.~~net~~/blog/2012/04/13/simplifying-a-map-layer-using-postgis-topology/ Simplifying a map layer using PostGIS topology] (strk's blog)		* [http://strk.kbt.io/blog/2012/04/13/simplifying-a-map-layer-using-postgis-topology/ Simplifying a map layer using PostGIS topology] (strk's blog)

	;Concepts:		;Concepts:

Neteler: Updated to G7.2

2017-01-18T13:15:46Z

Updated to G7.2

← Older revision		Revision as of 13:15, 18 January 2017
Line 100:		Line 100:
	[[Image:topo-geo-grass.png\|thumb\|800px\|center\|Additional GRASS-related tables in PostGIS Topology schema]]		[[Image:topo-geo-grass.png\|thumb\|800px\|center\|Additional GRASS-related tables in PostGIS Topology schema]]

	Storing GRASS-related topological data in DB can be disabled by <tt>TOPO_GEO_ONLY</tt> option, see {{cmd\|v.out.postgis~~\|version=70~~}} for details.		Storing GRASS-related topological data in DB can be disabled by <tt>TOPO_GEO_ONLY</tt> option, see {{cmd\|v.out.postgis}} for details.

	GRASS also stores additional metadata in 'topology.grass' table, currently only bounding box of the map.		GRASS also stores additional metadata in 'topology.grass' table, currently only bounding box of the map.
Line 214:		Line 214:
	Currently GRASS supports converting only selected vector layer into PostGIS table, not the whole vector map (see more about vector layers and maps [[Vector Database Management#GRASS GIS vector management model\|here]]).		Currently GRASS supports converting only selected vector layer into PostGIS table, not the whole vector map (see more about vector layers and maps [[Vector Database Management#GRASS GIS vector management model\|here]]).

	In the example below GRASS vector map 'urbanareas' (layer '1' which is default) is converted into PostGIS table 'ua' located in 'pgis_db' database using {{cmd\|v.out.postgis~~\|version=70~~}}. Topological export is enabled by <code>-l</code> flag. Exported data is linked automatically as GRASS vector map by <code>olink</code> parameter. In this case there is no need to create a link using {{cmd\|v.external~~\|version=70~~}}.		In the example below GRASS vector map 'urbanareas' (layer '1' which is default) is converted into PostGIS table 'ua' located in 'pgis_db' database using {{cmd\|v.out.postgis}}. Topological export is enabled by <code>-l</code> flag. Exported data is linked automatically as GRASS vector map by <code>olink</code> parameter. In this case there is no need to create a link using {{cmd\|v.external}}.

	From CLI:		From CLI:

	v.out.postgis -l input=urbanarea ~~dsn~~=PG:dbname=pgis_db olayer=ua olink=ua_pg		v.out.postgis -l input=urbanarea input=PG:dbname=pgis_db olayer=ua olink=ua_pg

	'''Important note:''' Without <code>-l</code> flag the vector data are exported as simple features and not as topological elements!		'''Important note:''' Without <code>-l</code> flag the vector data are exported as simple features and not as topological elements!
Line 227:		Line 227:
	<center>		<center>
	{\|		{\|
	\|valign="top"\|{{fig\|wxgui-v.out.postgis-1\|GUI dialog of {{cmd\|v.out.postgis~~\|version=70~~}} module (required parameters)}}		\|valign="top"\|{{fig\|wxgui-v.out.postgis-1\|GUI dialog of {{cmd\|v.out.postgis}} module (required parameters)}}
	\|valign="top"\|{{fig\|wxgui-v.out.postgis-2\|GUI dialog of {{cmd\|v.out.postgis~~\|version=70~~}} module (other parameters)}}		\|valign="top"\|{{fig\|wxgui-v.out.postgis-2\|GUI dialog of {{cmd\|v.out.postgis}} module (other parameters)}}
	\|}		\|}
	</center>		</center>
Line 236:		Line 236:
	There are two options.		There are two options.

	'''First option''' is traditional way which requires converting vector data into GRASS topological format using {{cmd\|v.in.ogr~~\|version=70~~}} and afterwards exporting GRASS topological data into PostGIS Topology by {{cmd\|v.out.postgis~~\|version=70~~}} module. See example below.		'''First option''' is traditional way which requires converting vector data into GRASS topological format using {{cmd\|v.in.ogr}} and afterwards exporting GRASS topological data into PostGIS Topology by {{cmd\|v.out.postgis}} module. See example below.

	v.in.ogr ~~dsn~~=zone.shp		v.in.ogr input=zone.shp output=zone
	v.out.postgis -l input=zone ~~dsn~~=PG:dbname=pgis_db olink=zone_pg		v.out.postgis -l input=zone input=PG:dbname=pgis_db olink=zone_pg

	'''Second option''' is based on external data format set by {{cmd\|v.external.out~~\|version=70~~}}. In this case output format is topological PostGIS (see [[#Set output vector format to PostGIS Topology\|set output vector format to PostGIS Topology]])		'''Second option''' is based on external data format set by {{cmd\|v.external.out}}. In this case output format is topological PostGIS (see [[#Set output vector format to PostGIS Topology\|set output vector format to PostGIS Topology]])

	v.external.out ~~dsn~~=PG:dbname=pgis_db options=topology=yes format=PostgreSQL		v.external.out input=PG:dbname=pgis_db options=topology=yes format=PostgreSQL
	v.in.ogr ~~dsn~~=zone.shp		v.in.ogr input=zone.shp output=zone

	In this case, the module {{cmd\|v.in.ogr~~\|version=70~~}} doesn't produce vector data in GRASS format, the data are directly stored in PostGIS Topology. The module also creates vector map given by <code>olink</code> parameter which points to the data stored in PostGIS database.		In this case, the module {{cmd\|v.in.ogr}} doesn't produce vector data in GRASS format, the data are directly stored in PostGIS Topology. The module also creates vector map given by <code>olink</code> parameter which points to the data stored in PostGIS database.

	v.info zone_pg		v.info zone_pg
Line 264:		Line 264:
	=== Set output vector format to PostGIS Topology ===		=== Set output vector format to PostGIS Topology ===

	Output format for vector data can be set by {{cmd\|v.external.out~~\|version=70~~}}.		Output format for vector data can be set by {{cmd\|v.external.out}}.

	From command line (note <code>options=topology=yes</code> which enables topological mode):		From command line (note <code>options=topology=yes</code> which enables topological mode):
Line 270:		Line 270:
	v.external.out output=PG:dbname=pgis_db options=topology=yes format=PostgreSQL		v.external.out output=PG:dbname=pgis_db options=topology=yes format=PostgreSQL

	Connection settings (username, password, or hostname) can be set by {{cmd\|db.login~~\|version=70~~}} or as a part of connection string (see <code>dsn</code> parameter).		Connection settings (username, password, or hostname) can be set by {{cmd\|db.login}} or as a part of connection string (see <code>dsn</code> parameter).

	From [[wxGUI]] menu {{GuiMenu\|File\|External formats\|Output vector format}} or from toolbar [[Image:layer-import.png]]		From [[wxGUI]] menu {{GuiMenu\|File\|External formats\|Output vector format}} or from toolbar [[Image:layer-import.png]]
Line 277:		Line 277:
	{{fig\|wxgui-v.external.out-pg-1}}		{{fig\|wxgui-v.external.out-pg-1}}

	As a result, every newly created vector map will be stored in the given PostGIS Topology database. Created PostGIS data are automatically registered in the current mapset as normal GRASS vector maps (similarly when the user creates link using {{cmd\|v.external~~\|version=70~~}}).		As a result, every newly created vector map will be stored in the given PostGIS Topology database. Created PostGIS data are automatically registered in the current mapset as normal GRASS vector maps (similarly when the user creates link using {{cmd\|v.external}}).

	=== Create simple features geometry from PostGIS Topology ===		=== Create simple features geometry from PostGIS Topology ===
Line 283:		Line 283:
	GRASS can automatically create simple features geometry when building topology over PostGIS Topology features. In example bellow we create buffer map from vector map 'roadsmajor'. The output vector map containing buffers is stored in PostGIS Topology database (<code>options=topology=yes</code>). By giving <b><code>options=simple_feature=yes</code></b> GRASS also stores in DB simple features geometry which is built from PostGIS topological elements (nodes, edges, and faces).		GRASS can automatically create simple features geometry when building topology over PostGIS Topology features. In example bellow we create buffer map from vector map 'roadsmajor'. The output vector map containing buffers is stored in PostGIS Topology database (<code>options=topology=yes</code>). By giving <b><code>options=simple_feature=yes</code></b> GRASS also stores in DB simple features geometry which is built from PostGIS topological elements (nodes, edges, and faces).

	v.external.out ~~dsn~~=PG:dbname=pgis_db options=topology=yes,simple_features=yes format=PostgreSQL		v.external.out input=PG:dbname=pgis_db options=topology=yes,simple_features=yes format=PostgreSQL

	We create buffers based on 'roadsmajor' vector map		We create buffers based on 'roadsmajor' vector map
Line 315:		Line 315:

	* [http://geo.fsv.cvut.cz/data/osgeorel/2013-04-fem-gis/landa-fem-gis-2013-04.pdf Working with PostGIS Topology in GRASS GIS] ([http://gis.cri.fmach.it/news/47/15/Seminar-Advances-in-GIS-data-processing-and-management/ Seminar: Advances in GIS data processing and management] at Fondazione Edmund Mach, Italy, 2013-04-13)		* [http://geo.fsv.cvut.cz/data/osgeorel/2013-04-fem-gis/landa-fem-gis-2013-04.pdf Working with PostGIS Topology in GRASS GIS] ([http://gis.cri.fmach.it/news/47/15/Seminar-Advances-in-GIS-data-processing-and-management/ Seminar: Advances in GIS data processing and management] at Fondazione Edmund Mach, Italy, 2013-04-13)
	* {{cmd\|v.out.postgis~~\|version=70~~}} manual		* {{cmd\|v.out.postgis}} manual
	* [[Working with external data in GRASS 7]] and {{cmd\|v.external.out~~\|version=70~~}} manual		* [[Working with external data in GRASS 7]] and {{cmd\|v.external.out}} manual
	* [[PostGIS]] support in GRASS GIS		* [[PostGIS]] support in GRASS GIS

⚠️Landa: /* Set output vector format to PostGIS Topology */

2015-11-23T09:42:28Z

Set output vector format to PostGIS Topology

← Older revision		Revision as of 09:42, 23 November 2015
Line 268:		Line 268:
	From command line (note <code>options=topology=yes</code> which enables topological mode):		From command line (note <code>options=topology=yes</code> which enables topological mode):

	v.external.out ~~dsn~~=PG:dbname=pgis_db options=topology=yes format=PostgreSQL		v.external.out output=PG:dbname=pgis_db options=topology=yes format=PostgreSQL

	Connection settings (username, password, or hostname) can be set by {{cmd\|db.login\|version=70}} or as a part of connection string (see <code>dsn</code> parameter).		Connection settings (username, password, or hostname) can be set by {{cmd\|db.login\|version=70}} or as a part of connection string (see <code>dsn</code> parameter).

⚠️Landa: new video

2013-12-12T14:39:58Z

new video

← Older revision		Revision as of 14:39, 12 December 2013
Line 310:		Line 310:

	{{YouTube\|qetGzrBgr74\|desc=Import VFK data into PostGIS Topology database}}		{{YouTube\|qetGzrBgr74\|desc=Import VFK data into PostGIS Topology database}}
			{{YouTube\|c2fOGJCI3Qk\|desc=Import Shapefile/DXF to PostGIS Topology}}

	== See also ==		== See also ==

⚠️Landa at 11:53, 3 December 2013

2013-12-03T11:53:21Z

← Older revision		Revision as of 11:53, 3 December 2013
Line 98:		Line 98:
	Additional topological data related to nodes, lines, areas, and isles are stored in separated tables, see figure bellow.		Additional topological data related to nodes, lines, areas, and isles are stored in separated tables, see figure bellow.

	[[Image:topo-geo-grass.png\|thumb\|~~640px~~\|center\|Additional GRASS-related tables in PostGIS Topology schema]]		[[Image:topo-geo-grass.png\|thumb\|800px\|center\|Additional GRASS-related tables in PostGIS Topology schema]]

	Storing GRASS-related topological data in DB can be disabled by <tt>TOPO_GEO_ONLY</tt> option, see {{cmd\|v.out.postgis\|version=70}} for details.		Storing GRASS-related topological data in DB can be disabled by <tt>TOPO_GEO_ONLY</tt> option, see {{cmd\|v.out.postgis\|version=70}} for details.

⚠️Landa at 11:52, 3 December 2013

2013-12-03T11:52:57Z

← Older revision		Revision as of 11:52, 3 December 2013
Line 96:		Line 96:
	* Isles are stored as faces (with id <= 0) (including universal face defined by PostGIS Topology)		* Isles are stored as faces (with id <= 0) (including universal face defined by PostGIS Topology)

	Additional topological data related to nodes, areas, and isles are stored in separated tables, see figure bellow.		Additional topological data related to nodes, lines, areas, and isles are stored in separated tables, see figure bellow.

	[[Image:topo-geo-grass.png\|thumb\|640px\|center\|Additional GRASS-related tables in PostGIS Topology schema]]		[[Image:topo-geo-grass.png\|thumb\|640px\|center\|Additional GRASS-related tables in PostGIS Topology schema]]

⚠️Landa at 11:27, 3 December 2013

2013-12-03T11:27:11Z

← Older revision		Revision as of 11:27, 3 December 2013
Line 281:		Line 281:
	=== Create simple features geometry from PostGIS Topology ===		=== Create simple features geometry from PostGIS Topology ===

	GRASS can automatically create simple features geometry when building topology over PostGIS Topology features. In example bellow we create buffer map from vector map 'roadsmajor'. The output vector map containing buffers is stored in PostGIS Topology database (<code>options=topology=yes</code>). By giving <code>options=simple_feature=yes</code> GRASS also stores in DB simple features geometry which is built from PostGIS topological elements (nodes, edges, and faces).		GRASS can automatically create simple features geometry when building topology over PostGIS Topology features. In example bellow we create buffer map from vector map 'roadsmajor'. The output vector map containing buffers is stored in PostGIS Topology database (<code>options=topology=yes</code>). By giving <b><code>options=simple_feature=yes</code></b> GRASS also stores in DB simple features geometry which is built from PostGIS topological elements (nodes, edges, and faces).

	v.external.out dsn=PG:dbname=pgis_db options=topology=yes,simple_features=yes format=PostgreSQL		v.external.out dsn=PG:dbname=pgis_db options=topology=yes,simple_features=yes format=PostgreSQL

⚠️Landa: /* Create simple features geometry from PostGIS Topology */

2013-12-03T11:26:13Z

Create simple features geometry from PostGIS Topology

← Older revision		Revision as of 11:26, 3 December 2013
Line 291:		Line 291:
	We check result by SQL statement by printing topogeometry data ('topo' column) and area size of created simple features polygons ('geom' column)		We check result by SQL statement by printing topogeometry data ('topo' column) and area size of created simple features polygons ('geom' column)

	~~db.select~~ sql="select fid,topo,st_area(geom) from roadsmajor_100~~" driver=pg database=pgis_db~~		<source lang=sql>
			select fid,topo,st_area(geom) from roadsmajor_100;
			</source>

			<pre>
			fid \| topo \| st_area
			-----+-------------+------------------
			1 \| (363,1,1,3) \| 100002017.849343
			</pre>

	== Screenshots ==		== Screenshots ==

⚠️Landa: /* Create simple features geometry from PostGIS Topology */

2013-12-03T11:25:03Z

Create simple features geometry from PostGIS Topology

← Older revision		Revision as of 11:25, 3 December 2013
Line 284:		Line 284:

	v.external.out dsn=PG:dbname=pgis_db options=topology=yes,simple_features=yes format=PostgreSQL		v.external.out dsn=PG:dbname=pgis_db options=topology=yes,simple_features=yes format=PostgreSQL

			We create buffers based on 'roadsmajor' vector map

			v.buffer in=roadsmajor out=roadsmajor_100 dist=100 --o

			We check result by SQL statement by printing topogeometry data ('topo' column) and area size of created simple features polygons ('geom' column)

			db.select sql="select fid,topo,st_area(geom) from roadsmajor_100" driver=pg database=pgis_db

	== Screenshots ==		== Screenshots ==

⚠️Landa at 11:16, 3 December 2013

2013-12-03T11:16:03Z

← Older revision		Revision as of 11:16, 3 December 2013
Line 279:		Line 279:
	As a result, every newly created vector map will be stored in the given PostGIS Topology database. Created PostGIS data are automatically registered in the current mapset as normal GRASS vector maps (similarly when the user creates link using {{cmd\|v.external\|version=70}}).		As a result, every newly created vector map will be stored in the given PostGIS Topology database. Created PostGIS data are automatically registered in the current mapset as normal GRASS vector maps (similarly when the user creates link using {{cmd\|v.external\|version=70}}).

	=== Create simple features from PostGIS Topology ===		=== Create simple features geometry from PostGIS Topology ===

	GRASS can automatically create simple features geometry when building topology over PostGIS Topology features. In example bellow we create buffer map from vector map 'roadsmajor'. The output vector map containing buffers is stored in PostGIS Topology database (<code>options=topology=yes</code>). By giving <code>options=simple_feature=yes</code> GRASS also stores in DB simple features geometry which is built from PostGIS topological elements (nodes, edges, and faces).		GRASS can automatically create simple features geometry when building topology over PostGIS Topology features. In example bellow we create buffer map from vector map 'roadsmajor'. The output vector map containing buffers is stored in PostGIS Topology database (<code>options=topology=yes</code>). By giving <code>options=simple_feature=yes</code> GRASS also stores in DB simple features geometry which is built from PostGIS topological elements (nodes, edges, and faces).