PostGIS is an extension for the PostgreSQL object-relational database that adds support for geographic objects.

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Can't import shapefile to PostGIS

Sorry if my question is double post with the previous. I have tried to browse but I think I still can't find the solution. I am using postgresql 9.4.1 and postgis 2.1(pg 94) and also qgis 2.4.0. All ...
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159 views

Speeding Up pgr_dijkstra using bounding box in PostGis2.0

I'm using PostGIS for the first time to calculate distances between two points, for a driving school booking system I am working on. I have loaded in all of the maps for Australia, but the query I ...
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93 views

suitable column Data-type for geojson data storage and processign in PostGis

I have a MySQL table with 2 columns, id, a unique geometry id, and GeoJSON stored as a varchar, eg, {"type": "Point", "coordinates": [116.4, 45.2, 11.1]} ...
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164 views

How do I create a spatial filter on a layer?

I have a layer that draws points in a PostgreSQL (PostGIS) database. The problem is, all points in the table are being drawn. I want to limit the points drawn to a spatial query. How do I limit the ...
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108 views

Problem with importing WKT to PostGIS

I'm trying to import WKT (http://polygons.openstreetmap.fr/get_wkt.py?id=2413177&params=0 - boundary of one of districts of Łódź) into PostGIS database and convert it to geometry. I've created ...
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141 views

set Default projection in postgis table

I've set the SRID 4326 for a table having geometry column, but when i insert a geometry without SRID, i get an error because no SRID specified is interpreted as -1 or 0, so how i can set a default ...
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1answer
449 views

How to create dissolved buffers in QGIS with PostgreSQL/PostGIS?

Creating a dynamic buffer in QGIS I use the following query: CREATE VIEW buffer40units AS SELECT gid, st_buffer(geom,40)::geometry(polygon, 31492) AS geom FROM point; Now I want to dissolve ...
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89 views

ST_Buffer with segment AND endcap parameters

Making a QGis plugin that buffers a line and I want to declare a high number of segments and a flat endcap. ST_Buffer(geom, 40, 25, 'endcap=flat') This doesn't work with both parameters entered, ...
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696 views

Map-matching GPS points to the road network!

I am quite a newbie in Postgres and Postgis so please be simple and clear :) I am trying to do a simple map-matching (or path-inference if you wish) of some GPS points. I am using postgres(postgis). ...
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57 views

Displaying KML data with a user selection

I want to web map some historical cyclones data which are now in KML files, file/year. So I want the user to select a year from a button and the KML files will be displayed on interactive map). I ...
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135 views

Create common vertexes between shared polygon boundaries in PostGis?

Given two polygon tables L1 (blue) and L2 (red) that share a common boundary but different amount of vertexes, how can one make the shared boundary identical (they should share the same vertexes) ? ...
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431 views

Can't connect to foreign SQL Server table from PosgreSQL using OGR_FDW

I'm using Windows 7, with PostgreSQL 9.3.6 installed and PostGIS 2.1.5. While I wish I could get everything into PostgreSQL, I can't and need to connect to another server running SQL Server. I need to ...
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1answer
78 views

QGIS GPS not editing offline database

I have a set of layers from PostGIS that I have converted to offline. I am attempting to edit them via GPS. If the layer is point data, then I can add in that data without issue. However when I go to ...
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106 views

PostGis - ST_AsRaster returning raster smaller than reference raster

I am trying to convert a point geometry to a raster using a reference raster: SELECT ST_AsRaster(my_points, ref_raster) FROM my_table This works fine except it is only returning a subset of the ...
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166 views

PostGIS: Is it possible to identify overlapping polygons in the same layer using their geomteries?

I have a single table containing the geometries of ~3 million polygons and I am looking to calculate the number of polygons that overlap with another. I know that you are able to do this in QGIS ...
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1answer
72 views

QGIS add layer not working

I have QGIS 2.8. I open up the database manager, connect to PostGIS, and then execute a query. The resulting query has an id column, a name column, a geom column, and a membership column. I click on ...
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1answer
104 views

PostGIS and Mobile Devices Maps

I'm still learning the world of GIS reading this Introduction to PostGIS. So far I understand things but since I have an idea that I plan to later work on, I found something that I didn't quiet grasp. ...
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57 views

Point Cloud footprint/wireframe layer - PostGIS

I'm using PDAL to import LAS files into PostGIS. The tutorial provided by boundless is great, and shows how to display the data in patches, but it doesn't cover displaying the table 'footprint'. I ...
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1answer
85 views

How can I select only the points in a mixed geometry column in postgis postgres

Table "public.eating_drinking" Column | Type | Modifiers --------+-------------------------+----------- osm_id | bigint | way | ...
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200 views

Calculate total line lengths within a polygon?

I have basically the same conundrum as How do i calculate line segment lengths within a polygon? but I'm working in PostGIS, not ArcGIS. Any pointers? This query seems to like it should work, just ...
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1answer
160 views

How do I calculate ST_Length in miles?

I am playing around with a map of bike lanes (so, lines) and trying to calculate the total number of miles of lane in each of a couple of regions. But I'm not even sure how to use ST_Length to ...
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508 views

How to import country administrative boundaries from OSM Planet to PostGIS Polygons

I need to import all world countries as polygons or multipolygons into PostGIS. Specifically, I need the administrative boundaries that are like this orange bubble around the actual land borders. ...
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100 views

PostGIS raster2pgsql problem

I ran into this problem in PostGIS: raster2pgsql -c -I -C -s 4326 -N -9999 -M -Y -F ./test2/*.tif rdem2 > rdem2.sql Processing 84/84: ./test2/dem2_4326_06_14.tif ERROR: ...
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156 views

Select points near polygon in Postgis

I'm trying to make a spatial query, but I think something is wrong with it: I have two tables, places (point) and cities (polygon) When I try to get the points within 500m to one point, there is no ...
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255 views

How to get extent of multiple geometries?

I can query a geometry extent like this: select ST_Extent(geom) from tableName; But sometimes I am querying geometries more than one. I am getting 5 points that different locations. So I wanto to ...
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118 views

I can't understand this ewkb type mask

I have the following ewkb strings from PostGIS: 01 01000020 E6100000 AECB9307F9D81240 0F2ADCE003704940 01 01000020 E6100000 7EAA0A0DC4920DC0 5AF0A2AF201F4440 I've been able to understand every data ...
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85 views

Find hotspot with highest density for two objects

I'm using PostgreSQL/PostGIS and I have an advanced type of query. My database contains two types of objects - let's say homes and crime. Is there a way that I can find the area with the densest ...
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58 views

How to create raster from table containing cell values in PostGIS?

I am having a table with integer values. These values are in between 0 and 2. I want to create a raster out of that table with integers as cell values. Or else how to create polygons out of that table ...
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137 views

QGIS Add PostGIS layer: restricting to single schema?

My primary PostGIS database has 12 schemas (schemae? TNIRN...), some of which have nasty-sized tables. The DB is on localhost, on my own machine. For the most part, the actual working tables are in ...
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1answer
80 views

POSTGIS query - extracting common point from polygon data

I have a polygon dataset and need to find the single common point where 3 polygons meet. I'm approaching this by creating duplicate tables and comparing them to the main one (polygon_table a). I've ...
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159 views

PostGIS Geography data type not displaying in QGIS

I am trying to display data held in the PostGIS Geography type on a map in QGIS. Whatever I do I can't get it to work. Here is the SQL that creates my data - a single point in London. CREATE TABLE ...
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270 views

How can I speed up a slow ArcGIS Server 10.2 - PostgreSQL (9.2) ST_Intersects query?

I am troubleshooting a slow st_geometry query in Postgres 9.2 that uses ST_Intersects--a basic Select from table where ST_Intersects type query. table_extent ...
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1answer
160 views

Postgis ST_Distance query returning inaccurate results

I am using the following query to retrieve records from a postgresql DB @services = Service.select("*, ST_Distance(services.lon_lat, ST_GeomFromText('POINT (lat lon)', 4326)) as ...
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130 views

GeoDjango: AttributeError: function 'GDALAllRegister' not found [closed]

Im trying to get started with GeoDjango. I am using this https://docs.djangoproject.com/en/1.8/ref/contrib/gis/tutorial/ tutorial. When I run "python manage.py migrate" This error occur: ...
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74 views

Mapnik performance - large polyline dataset

I'm working with a very large set of polylines - contour data - to be rendered with Mapnik. (The contours are generated using gdal_contour from SRTM data.) At present I'm storing them in PostGIS and ...
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2answers
100 views

SRID is messed up when google-maps layer is added

I've some problems with using a PostGIS layer within QGIS. First of all, I had this same problem on both QGIS 2.4.0 and 2.6.1 I cannot display the Google Maps layer AND my PostGIS layer together. ...
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1answer
3k views

Store a GeoJSON FeatureCollection to postgres with postgis

I am new to GeoJSON. I have a GeoJSON features collection as shown and would like to store it in postgres table (testtable). My postgres table has a serial id and geometry column. { "type": ...
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1answer
213 views

ST_MakeLine within CartoDB.js

I'm building an interactive map using CartoDB.js in an HTML page. I have the user input an address that gets geocoded. I then use the user's lat/lon coordinates to perform SQL queries on CartoDB. The ...
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392 views

Problem with a PostGIS trigger

I'm trying to update a lat and lon columns each time I insert a point with a trigger, but I don't know why I get an error. This is the syntax I'm writing: CREATE OR REPLACE FUNCTION update_tg2() ...
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340 views

pgrouting pgr_dijkstra forcing route along a selected edge?

I have routing working where a user clicks 2 points on the map, I find the closest vertex to those 2 clicked locations and pass that to a pgr_dijkstra function. What I would like is give the edge a ...
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1answer
129 views

Calculating Distances Between Geometry Columns of Differing SRIDs

I am attempting a relatively simple task but have been running into trouble. I have two tables, one which has lat and lon points which were geocoded using google (SRID 3857) and another table which ...
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49 views

Geoserver - How to make a psql-backed timestamp that uses timezones

I'm working on an application that extends geoserver and am frustrated as I'm trying to define a SimpleFeature that has timestamps that include timezones. I've tried declaring my timestamp field ...
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1answer
50 views

Plotting Street Map for City - Where do I start?

Please excuse my ignorance of this and if I break any of the rules please be gentle as this is my first post here and I'm not GIS expert either. I need people to steer me in right direction so that I ...
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105 views

Not able to get the PostGIS Layer Viewer running in pgAdmin or command line

I've installed PostGIS Layer Viewer as a plugin for pgAdmin. I've downloaded postgis_viewer.py from the official repository on GitHub! and followed the install instructions described on Web site!. ...
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101 views

I am getting error in PostGIS 'function st_clip(raster, integer, geometry) does not exist'? [closed]

I have to find the count of the number of pixels in a given band of a clipped raster. For clipping, I am using ST_clip(). Through clip function raster is clipped with a polygon. I am getting ...
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1answer
289 views

error importing shp into postgis using ogr2ogr

I run an automated script that copies a number shapefiles into PostGIS. I have a problem with one dataset which fails during the export. As the roads.shp dataset is maintained by someone else, I ...
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1answer
201 views

How to get pixel values/cell values for stored raster files in postgis?

Raster files in tiff format are storing into database.However I gets only an attribute table. Is there any way to retrieve pixel values/cell values in the table. I have used raster2pgsql command for ...
3
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1answer
190 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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1answer
155 views

Geoserver GeoWebCache caches tiles of incomplete layers

I have data in a PostGIS database that is being pulled into Geoserver using a PostGIS (JNDI) store. The dataset I am using is a continuous polygon grid, but the dataset itself isn't all that large. ...
3
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1answer
216 views

PostGIS is not seeing any GDAL drivers

I've tried setting POSTGIS_GDAL_ENABLED_DRIVERS=ENABLE_ALL as an environment variable. As well as running SET postgis.gdal_enabled_drivers = 'ENABLE_ALL'; from psql. -- (With a pg_ctl restart after ...