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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60 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
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0answers
67 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 ...
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2answers
95 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 ...
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1answer
24 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: ...
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0answers
26 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 ...
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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 ...
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1answer
1k 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 ...
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1answer
245 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 - ...
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121 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 ...
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1answer
59 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
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1answer
84 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 ...
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1answer
58 views

how to insert coordinate of province to postgresql?

i need insert to database this area sample: [ [ [ 50.227886556627098, 31.15709614260982 ], [ 50.227886335531331, ...
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0answers
28 views

Can the correct TIGER Line Id be returned for an address from the PostGIS Tiger Geocoder?

After reviewing the PostGIS Tiger Geocoder documentation, I don't see a method of returning the TIGER Line Id for the address. I would assume this is information is available internally as part of ...
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2answers
106 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 ...
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1answer
6k 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 ...
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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
103 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 ...
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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. ...
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1answer
27 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
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1answer
174 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 ...
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3answers
173 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 ...
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0answers
88 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 ...
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1answer
183 views

What PostGIS [topology] provided tools may be used for data quality assurance?

I'm learning about techniques to ensure GIS data quality. Googling around, I've found a few papers about theory and best practices (here and here), and a couple of short presentations about the topic ...
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2answers
129 views

Loading data using QGIS to PostgreSQL database

I am trying to import a shapefile using desktop QGIS to postgreSQL database using the import shape file to postgresql database tool but it raises the following error: Problem inserting features ...
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1answer
77 views

How do I project a point stored as Lat / Lon to a state system?

I have some points stored as WGS84 (EPSG:4326) data. I want to write a SELECT statement to return the projected values, in EPSG:2811, and unprojected values. Here is my table SQL: CREATE TABLE ...
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0answers
57 views

Postgis - st_MakeLine and st_lineLocatePoint

Lets explain, I have 4 points (1,2,3,4), and I need to visit clients (A, B, C, D). So, I need to use st_makeline with (1,2,3,4,3)... Now I have to get % position from A,B,C,D; but in visit order. ...
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1answer
460 views

Unable to create Polygon using Geodjango admin interface

I am new to GeoDjango. I have created Admin interface for my Model. It loads correctly. I am also able to draw the Polygon on map(At client side) but when I save It tells me Invalid input and throws ...
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0answers
62 views

Add new feature to postgis via geoexplorer

I have a polygon table in postgres/postgis and I set up some fields to not allow null values. My problem is when I add a mew polygon via opengeo geoexplorer (myviewer sdk) and keep these fields empty ...
0
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1answer
32 views

problem in PostGIS Name of the system used for Points and how to get distance between to point?

I have started to work on a project in PostGIS. I have a table with a geometry points in which points saved like this : "010100000089F511C671C01E4162327E2A83545341" and I have translated this ...
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2answers
137 views

Neighbors within distance from every row

I have a research project of 180,000 entries and I need to calculate the number of neighbors (points from the same table) that exist within a 300 meter radius for each point. My method is very slow, ...
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0answers
13 views

PSQL: Setting maxspeed to all highway tags having 'highway' text= NULL AND 'maxspeed' text = NULL?

Hello everyone, I am trying to create a procedure in postgresql using functions of postgis extensions where I can first search and find all the rows having an empty 'highway' tags AND ...
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1answer
103 views

OpenLayers WFS-T tinyows insert transaction: error GID value

I try to implement insertion of new point using Openlayers v2.13 saveStrategy calling tinyows which implements the WFS-T transaction; I use the example from ...
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0answers
22 views

postgis 2.x geometrycollection and multi

I want to gather differents geometries in a table. So I transformed a multipolygon geometry in a geometrycollection. Now if I can insert differents geometries, I lost the capability of insert ...
0
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1answer
164 views

How to create buffer around point having projection 4326

I am trying to create buffer (in meters) around point(long lat alt) which is in projection 4326 with below code. But it is not giving expected output. SELECT ...
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1answer
126 views

How to create Spatial Reference System in QGIS?

I have some Attribute and the coordinate and the coordinate reference system. I want to create a DBmanagamet form my spatial data. To do that I want to create one table with name Spa_ref_sys, but I ...
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0answers
77 views

Problem with ST_SummaryStats, ST_Buffer, and casting between geometry/geography types

I have a test raster that covers the world ((-180 90), (180 -90)). The SRID is WGS 84 (EPSG:4326). Values for cells in the north-western quadrant ((-180 90), (0 0)) are random integers in the range 1 ...
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2answers
170 views

How to get the number of polygons of a geometry in PostgreSQL

How can I get the number of polygons that form a geometry in PostgreSQL? For example U.S map has a lot of islands in addition to its main lands. I want to count these islands plus the main lands.
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3answers
4k views

Loading geotiffs into PostGIS using raster2pgsql

I have an issue with loading some Ordnance Survey raster data into PostGIS. I have been using the following raster2pgsql command to load a tif that I have placed in my C:\Program ...
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1answer
90 views

Incorrect lat / lon conversion from utm

I used this website to determine that the SRID for my shapefile is 3857. Following that information, I used the shp2pgsql utility to convert my shapefile into the sql I need to insert into PostreSQL ...
0
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2answers
151 views

Find closest points in routing network for a set of points to pick shortest route

I have the following WITH SQL Query which does select a set of filling stations along a route within the distance of 1000m. In the SQL statement I fetch 1 Point from the station and search the closest ...
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1answer
227 views

How to detect gaps in a MultiPolygon table with Postgis?

I have mapping of land use. In it, I need running topology to detect gaps between polygons. Is there postgis's function to do this? Thanks
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0answers
80 views

Automatically generate random polygons with a given number of vertices

Updated to make it clear. What would be the fastest way to generate a random polygon in PostGIS with a specific number of vertices? I want to create a PostGIS function like GeneratePolygon(1000, ...
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1answer
55 views

Can I make tiles of a raster in postgis?

I am doing some work on dtms in postgis. To import the dtm, I snipped it into tiles and the work directly on the dtm works fine. Then I calculated aspect and slope of the dtm and got some bad ...
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0answers
120 views

Create polygons enclosing same number of points on PostGIS

I have a geodatabase on Postgis with points representing customers, what i need is give a number of customers, lets say 100 and it need to generate polygons enclosing 100 clients each one. I only ...
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2answers
6k views

What is the unit used in ST_Distance()?

I wonder what the unit is of the float being returned from ST_Distance. In the documentation it says: ...cartesian minimum distance (based on spatial ref) between two geometries in projected ...
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4answers
2k views

What does the “service” box in the PostGIS connection dialog stand for?

Can sоmеbody explain me what to write in the "service" box when connecting to the local DB. QGIS Lisboa and Postgres are installed.
3
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1answer
209 views

How to import a GeoTIFF into PostGIS without raster2pgsql

I know that one can import GeoTIFF into PostGIS via raster2pgsql. I was wondering if there is any easy way (as a sequence of SQL statements) to do the same without resorting to the command line tool? ...
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3answers
190 views

Convert SRText To PROJ4TEXT

I'd like to convert the following for updating my spatial_ref_sys table. ...
3
votes
1answer
104 views

PostGIS strange difference in distance calc from different point defenitions

I have a working POSTGIS database, loaded Dutch CBS data using shp2pgsql and now I want to map lat,lon coordinates to multipolygons. All examples I see use lon lat coordinates but if I do so I get ...
1
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1answer
121 views

What do pixeltypes in PostGIS raster mean?

I'm trying to build a raster in PostGIS from a vector layer and I was curious as to the meaning of pixeltypes in the raster geometry? How does it effect my raster?