Version 2.0 of PostGIS brought a heavy set of new extensions for the PostgreSQL object-relational database, adding greater support for spatial objects.

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2
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1answer
429 views

Creating GeoJSON from Postgres

We are transitioning from Google Maps to Mapbox. Mapbox is a proponent of geoJSON and uses it extensively, so we are considering adopting it for all of our maps. An issue is the creation of the ...
2
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2answers
45 views

PostGIS - raster and bands

I have several images from different times and for every time I have three types of image (temperatureA, temperatureB, pressure). Should I store them as every time as band in a single raster with N ...
2
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0answers
81 views

Dijkstra's Algorithm direction issue

I am trying to implement Dijkstra's algorithm, my query is working fine if I set direction parameter to false. I have to consider the direction of travel while calculating route from point A to point ...
1
vote
1answer
73 views

postgis - wrong ST_Distance with geography points [closed]

I'm trying to calculate the distance between to geographical points, but the calculated distance is bigger than the real one (from Google Maps). The location column in postgresql is define as ...
2
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0answers
40 views

Add bands or new raster column in Postgis?

Would it be faster to work with a new band or a new raster column for a raster dataset in Postgres with new pixel values, assuming that the size, extent and everything else relevant remains constant? ...
3
votes
2answers
348 views

Is there a way to change ST_asGeoJSON return values?

The function ST_asGeoJSON returns something like: "st_asgeojson": { "type":"MultiLineString", "coordinates":[ [ [-3.13512629299993,39.7174353130001], [-19....
0
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2answers
69 views

Finding vertex in comon with most polygons in PostGIS?

I have a table with polygon geometry, in this case representing counties. I'm trying to figure out how to write a query that returns vertices sorted by the number of polygons that share that vertex. ...
1
vote
1answer
304 views

Delete all data from a PostGIS topology

I need to delete everything (faces, nodes, edges, anything I'm not thinking of) from a PostGIS topology, but I want to keep my database schema (schemas, tables, columns, sequences, etc.) intact. Is ...
0
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1answer
104 views

transform geometry PostGIS column with unknown geometry type

I run PostgreSQL 9.1 and PostGIS 2.0. I have a table that contains one geometry column. But that column contains point, polygons lines, etc. So I set it like so, ALTER TABLE jake ADD COLUMN ...
5
votes
1answer
307 views

Hitting Memory Limits of PostGIS ST_ConcaveHull / Incomplete Shrink Wrap

I am trying to use PostGIS 2.0 on Postgres 8.4 to do some mapping. I am working with the NOAA Shapefiles, specifically their US States & Territories file located here: http://www.nws.noaa.gov/...
1
vote
0answers
42 views

Resuming an osm2pgsql import to postgres [closed]

I was doing an import of the north american data with osm2pgsql using sudo ./osm2pgsql -c -S /home/osmNA/nfs/osmNA/osm2pgsql/default.style --slim -d addressNA --flat-nodes flat-nodes.bin --number-...
2
votes
1answer
102 views

Postgis: intersection between geometry and geography

I am trying to detect if a geometry and a geography intersect or not. The problem is I cannot find such a method. There only is: boolean ST_Intersects( geometry geomA , geometry geomB ); boolean ...
0
votes
1answer
51 views

How do I intersect a point with a shape?

I have a table in Postgresql / PostGIS containing county geometries. This table was created by importing a shapefile. I verified the geometry was imported successfully by importing the table into QGIS ...
0
votes
1answer
103 views

function st_length3d(geometry) does not exist

Whenever I execute this query: SELECT ST_Length3D(ST_GeomFromEWKT('LINESTRING(0 0 0,5 0 3,5 10 5)')); Postgresql is throwing an error: ERROR: function st_length3d(geometry) does not exist SQL ...
1
vote
0answers
309 views

PostGIS is already installed in schema 'public', uninstall it first

I am having problems adding postgis to my database. I'm following the instructions from here: http://postgis.net/docs/postgis_installation.html#idp32328352 (That said, I have combined some previous ...
3
votes
2answers
387 views

Trouble using ST_Difference to remove overlapping features

I am trying to use ST_Difference to create a set of polygons (processing.trimmedparcelsnew) that do not contain any of the area covered by another set of polygons (test.single_geometry_1) using ...
4
votes
1answer
2k views

How to design model in Django using GeoDjango?

I am using Postgresql 9.0 and PostGIS 2.0. I am using Django 1.3 and GeoDjango. I have a model with id, latitude, longitude and placename. All the places are in the USA. My requirement is following: ...
1
vote
1answer
100 views

A few PgRouting database design questions

Does someone know how the cost field in PgRouting is calculated? What are 'source' and 'target' good for? 'osm_source_id' and 'osm_target_id' contain the same information using different numbers. Is ...
2
votes
2answers
632 views

Collecting multipolygons into a single multipolygon with ST_Collect() in PostGIS

I would like to collect 50,000 individual multipolygons into one big multipolygon. Unfortunately when I perform ST_Collect(geom) it bundles them into a geometry collection and cannot be cast as ::...
3
votes
2answers
1k views

Cleaning geometries in PostGIS?

I am trying to do some processing on some very large polygon layers. However I am running into various geometry errors such as: NOTICE: Ring Self-intersection at or near point 470396.52017068537 ...
1
vote
1answer
135 views

Set Tolerance in Postgis

is there anyway to set tolerance in Postgis, in Arcgis tolerance is the minimum distance which could separate two points, if the distance between them is smaller than the tolerance so the points are ...
1
vote
0answers
108 views

Can QGIS handle EMPTY geometries?

I am writing a plugin and have a postgis table which has EMPTY geometries in the geom column. MULTILINESTRING EMPTY I am having crashes which just close QGIS. I have narrowed it down to the EMPTY ...
0
votes
1answer
86 views

Problem importing sqlite into Postgres (with PostGis) using ogr2ogr

I am trying to import a very large sqlite file into Postgres SQL 9.3. The first tool I tried to use was OGR2GUI (http://www.ogr2gui.ca/). The 64 Bit version does nothing, whilst the 32 bit version ...
0
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0answers
53 views

How do I design a database for storing GPX tracks and supporting spatial queries? [duplicate]

I have a series of GPX files that contain 1...n tracks. Each track contains roughly 5k - 10k points. The GPX files do not contain waypoints or routes. I want to design a database with the following ...
0
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1answer
94 views

ST_Dwithin Source Code

I am looking for the st_dwithin postgis source code. I want to learn the way postgis determines whether a given geometry is within a given radius to another geometry.
4
votes
1answer
274 views

Updating SRID (Update_GeometrySRID) does not alter polygons (when it should)

I am trying to change the SRID of polygons layer, but I'm having trouble visualizing the result. I the SRID is misreported the shapefile I used to import into PostGIS. The metadata says the ...
3
votes
1answer
665 views

PostGIS: ERROR: lwpoly_from_lwlines: shell must have at least 4 points

I have achieved to close lines in order to build a polygon with: st_addpoint( st_makeline(geom ORDER BY .cd_noseq), st_pointn( st_makeline(geom ORDER BY cd_noseq), 1) ) but ...
8
votes
1answer
198 views

Building a polygon over a reachable area

I am currently working in the field of isochrones and the underlying algorithms. What now causes problems is not the calculation if the isochrone itself, but the visualization of the results. The ...
5
votes
3answers
2k views

How to find lat/lon values for every pixel in a GeoTIFF file?

I want to a store GeoTIFF file pixel by pixel in the database. I need to store pixel values along with the lat/lon of that pixel on the GeoTIFF image. Is it possible to do that?
1
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0answers
80 views

What is the fastest way to select oldest, unique geometry from a table containing duplicates in PostGIS?

I have an output from an ArcPy arcpy.Union_analysis operation and for the overlap polygons that were created I need to select out the oldest feature (along with the attributes). The result is 75740 ...
2
votes
0answers
93 views

PyQgis - Adding attributes to a POSTGIS layer

After reading @underdark's answer to this question on creating a new vector layer and @Matthias Kuhn's to this one on field calculation, I wrote a script that allows me to calcultate the mean arrival-...
2
votes
2answers
125 views

Is it possible to georeference raster stored in Postgis?

I'm looking to store a huge raster aerial image (400 Gb) into Postgis, but before storing it i like to know how i could georeference or rectify raster stored in postgis ? is there any Qgis plugins ...
0
votes
1answer
25 views

PGR_Djikstra function error

I'm trying to find a shortest path between 2 nodes using djikstra method but it keeps saying ERROR: Error, query must return columns 'id', 'source', 'target' and 'cost' this is my query: ...
1
vote
0answers
32 views

find nearest point to a point in another table

This similar, but not quite the same as this question. I need to pick, regardless of distance, the closest 'n' points to a given point in another table, using postGIS. Imagine a table with city ...
3
votes
2answers
3k views

PostGIS: Convert meters to arbitrary spatial reference units?

I'm writing a query that needs to be able to work with data of any SRID. The basic problem is very simple - I get two pieces of information: A point (SRID = 900913) A distance (unit = meters) I [...
2
votes
1answer
2k views

Having trouble connecting QGIS with postgres database with postgis extension [closed]

I am working on Ubuntu Precise with postgresql version 9.3 and postgis 2.0. After initially starting my postgres database and eventually getting permission errors that would prevent postgres from ...
2
votes
1answer
423 views

connecting Arc 10.3 to a PostGIS database “the coordinate system identifier is invalid” [closed]

Has anyone had any success directly connecting Arc 10.3 to a PostGIS/postgres database, where the geometry type is 'geometry'? I am able to connect and view the tables, but I am unable to view them - ...
0
votes
0answers
179 views

Why is Geoserver publishing my WMS layer in WGS84, when I have specified WyLAM?

I am trying to publish a WMS layer from Geoserver, based on a table in a PostGIS dastabase. The projection of the original source data is "WyLAM" (EPSG:8155). It seems that no matter which options I ...
3
votes
1answer
72 views

Prevent PostGIS Topology from splitting edges on line insert

I'm dealing with a large amount of road data represented with PostGIS Topology types. Anytime I add an edge over another edge, the edge is automatically split and a new node is created at the ...
7
votes
1answer
111 views

Why is there an upper limit to the SRID value in the spatial_ref_sys table in PostGIS 2.1?

I was trying to insert a reference system in PostGIS from http://spatialreference.org/, and got a constraint violation for spatial_ref_sys_srid_check. I checked that constraint and found that, when ...
0
votes
1answer
80 views

how to insert coordinate of province to postgresql?

i need insert to database this area sample: [ [ [ 50.227886556627098, 31.15709614260982 ], [ 50.227886335531331, ...
1
vote
2answers
137 views

How to transfer large amount of OSM data to postgis using osm2pgsql?

I am new to using Openstreetmap data and PostGIS database. I learned how to use osm2pgsql and transferred osm data for a small city to PostGIS database and worked fine. The problem is that when I try ...
3
votes
1answer
13k views

How do I resolve “relation does not exist”

I have a view, named PointsForGpxExport, that contains points I want to export to a GPX file. The ogr2ogr command I'm trying to use for the export is included below. When I run the command, a GPX file ...
0
votes
0answers
23 views

map doesnt shown up in css page

I use postgreSQL 9.2, postgis 2.0 and 2.1, pgrouting 2.0, and I connect it with css page (localhost) but the map from pstgreSQL database doesnt shown up, can anybody help me? MAP NAME PADANG # ...
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0answers
148 views

Publishing Geoserver WMS on Drupal 7 using openlayers module not working

I'm unable to overlay my WMS layer published from geoserver on map. Im using openlayers module in drupal 7 configured with geoserver + postgis. Im using EPSG:3857projection. Also the Geoserver module ...
7
votes
2answers
2k views

Postgis 2.0 upgrade problem with postgres data?

I have a serious problem: on Wednesday, April 2 OpenSUSE 12.1 is updated, and the package was to update the PostGIS-a version 1.5.3 to 2.0.0. After this operation, Postgres does not display records. ...
1
vote
1answer
29 views

geometry_column table not automatically exist

I use PostgreSQL 9.2 but geometry_column table not automatically exist like spatial_ref_sys table, but if I use PostgreSQL 9.1 it's exist. How to make geometry_column automatically exist in PostgreSQL ...
3
votes
1answer
196 views

Why doesn't my spatial index work?

I have a table with 50 million test points. The points are stored as latitude / longitude with SRID = 4326. The create script for the table: CREATE TABLE points ( name character varying, point ...
4
votes
3answers
292 views

How can I export points as GPX?

I have some point data in PostgreSQL / PostGIS. How do I export the data to a GPX file? I looked for commands similar to ST_AsGML and ST_AsKML but could not find anything to convert to GPX (like a ...
1
vote
0answers
108 views

Is there PostGIS equivalent to arcpy.sa.Slice() function?

I have an existing system built on an 8.3 PostgreSQL database which uses a ArcGIS - Spatial Analyst for a couple of raster operations. The system is moving to PostgreSQL 9.2 and I'm evaluating if the ...