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

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What can I use to generate an interconnected graph from a series of coordinates?

I have a table containing latitude and longitude coordinates, and I'd like to be able to build an interconnected graph from it to use with pgRouting. Is there an existing feature of postGIS or ...
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46 views

Import point cloud into PostgreSQL/ pdal pipeline fails

I have a point cloud dataset that I would like to upload to my postgres/postgis database. I followed this tutorial and I could install everything without problems (on ubuntu 14.04. On ubuntu 12.04 ...
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Unable to Display Postgis Database Table Geometry Column Points in Geomoose

I'm a beginner in this field.I want to plot the postgis database table geometry column in geomoose but it is showing a pink tile.Through an android device we are pushing latitude and longitude to ...
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31 views

postGIS st_equals function not working as expected

I have a situation where I need to find out if a geometry being imported into a postGIS 2.1 database matches one drawn previously (i.e we want to know if the imported geometry is less up-to-date than ...
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21 views

How does ST_SnapToGrid work using nearest neighbor interpolation?

I have rasters in a PostGIS database that are not necessarily aligned (some rasters offset from the grid). I want to use ST_SnapToGrid to align all rasters to the same grid but have some questions ...
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How does `ST_Union` treat NULL values in a raster?

My question is about how ST_Union of rasters containing NULL values are handled. For example suppose I have two rasters that intersect but the values of the intersection are NULL in one of the ...
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34 views

Densifying OpenStreetMap (OSM) network nodes?

I am working with osmconverter to convert osm files(*.osm) to *.pbf, then i use osm2po to get sql file that run into PostGis to get a network table. The last step is to run a createTopology ...
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66 views

How to create an exact tracking route from GPS data with animated icon?

Probably this is not purely GIS related question, its related to developing issues. I am just asking if there is any kind of suggestions from Gurus. I am building an tracking application where GPS ...
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51 views

Remove specific points from linestring postgis

I am working with a data set that has been using the (0 0) point to pad any points that were missing when the linestring was created. So now the query SELECT id, route as line FROM trips ...
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22 views

pg_dump Database that was populated with osm2pgsql

Is it possible to dump a postgres database that was created with osm2pgsql and a .osm.pbf file with pg_dump and import this into a remote postgres database? After running osm2pgsql the database is ...
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57 views

Help serializing a postGIS query to geojson

I have a query which I would like to serialize to geoJSON: select article_title, pub_date, city, geom from article, location where article.id = location.id; I can serialize the geom field easily ...
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49 views

Check if point is inside unclosed linestring using POSTGIS ST Functions [closed]

I have a table with spatial data. This table contains a single record which is a unclosed linestring. I calculated the Centroid of this geometry using query SELECT ST_AsText(ST_Centroid("geom")) ...
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31 views

Converting spatial data to table of vertices using PostGIS?

I have a spatial data table in PostGIS 2.1 that looks like this: Geom | type | cost POLYGON(0 0,1 1,2 2)| A | 123 POLYGON(3 3,4 4,5 5)| b | 123 I am trying to create a ...
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117 views

How fast should I expect PostGIS to geocode well-formatted addresses?

How fast should I expect PostGIS to geocode well-formatted addresses? I've installed PostgreSQL 9.3.7 and PostGIS 2.1.7, loaded the nation data and all states data but have found geocoding to be much ...
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27 views

Utilizing OSM Data in a Postgres/PostGIS database in ArcMap

I've been trying for over a week now, and I'm not sure what i'm doing wrong and I haven't found the answer yet. I am trying to display and symbolize the OSM dataset over Jordan in ArcGIS for Desktop ...
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56 views

How to change the “application_name” of a PostGIS-connection in QGIS?

PostGIS offers a view called pg_stat_activity, where you can see all the active connections to the database. This view includes the interesting column application_name. When a connection comes from a ...
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39 views

How to create regular point grid inside a polygon in Postgis without knowing cell size but cell number?

I need to create a grid within a polygon like it is done in How to create regular point grid inside a polygon in Postgis? There a function is created to draw the grid points. But necessary to know ...
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32 views

QGIS DB Manager - load as new layer not loading

After successfully running an SQL query on two tables and some results in 3 columns, I would really like to be able to display it in the canvas. Apparently, that function is not doing anything, not ...
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36 views

PostGIS 3D bounding box query that envolves all 3 axes (xyz)

I have some experience with PostgreSQL, but not with PostGIS, and for the life of me I can't make my bounding box take the Z axis into account. I have a points table with XYZ columns. I add another ...
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72 views

Number of Neighbors Around a Point

I need to get a count of neighbors within 100m for each point in a set of 250 million points. The result would have the id of each point accompanied by the number of neighbors around them. Can this be ...
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1answer
28 views

Best way to filter points given a starting point and max travel time

I have a database of about 1M geolocated addresses and I'm looking for a way to sort/filter these records based on a starting point and max travel time. Ex: "find every baker shop within 30 min ...
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23 views

Merging DEM files using PostGIS

I have several DEM files and I want to merge them to create a mosaic. I found the St_Union(raster) or St_MemUnion(raster) functions but I don't know how to use them. Are there any other solutions?
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82 views

How do I explode a MultiLineString using ST_Dump() in PostGIS?

I want to do what this blog post does: explode a MultiLineString into individual LineStrings. I'm using CartoDB but don't get individual LineStrings as the result of my query. I still get a ...
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34 views

OSM Bright Cartography XML

So I've successfully setup a tile server as described here: https://switch2osm.org/serving-tiles/manually-building-a-tile-server-14-04/ What's troubling is the lack of clarify surrounding OSM Bright ...
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polygonize some raster pixels based on their value in PostGIS

I need to extract and polygonize only those pixels of a raster that have a value (e.g.) greather than 2000.0 The reason is that I wish to do an operation like the following one (which is done only on ...
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39 views

Use QGIS and Qt dialog forms

I have a QGIS project where there are plots with a attributes like name of the owner, address of the owner, cultivate, and so on. This plots are read from a PostGIS database. The future users of this ...
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23 views

Using virtual or temporary geometry with PostGIS and pgRouting

I am attempting to find the shortest/fastest routes from GPS point to GPS point as described in this post: Create closest point on multilinestring to use in shortest_path() I have seen many solutions ...
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Displaying multiple features from a geoserver layer with time and style in a KML

I have 4 datasets organized in a PostGIS database each of the same geometry and location except they are at different times. They each have a corresponding datetime field. I can load these into a ...
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Selecting all pixels above a given value in a raster in PostGIS

I have a raster with one band whose value represents the date of the occurrence (a sequential integer). This raster file gets updated regularly, and each time that happens, I need to run a process ...
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63 views

Rendering TopoJSON in Leaflet from GeoJSON PostGIS output?

I'm using the query found here SQL query to have a complete geojson feature from PostGIS to get a geojson that I can display on a leaflet map. However, the amount of data is kinda big and the ...
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42 views

OL3 doesn't display the wms Layer

This is pretty much related to the question asked in the following link How to add Mapserver WMS to Openlayers 3 I followed the example in ...
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Merge raster tiles in PostGIS

I have several raster tiles that are adjacent and non-overlapping, so they form a mosaic. I am trying to merge two adjacent rasters using PostGIS but am getting an error that they do not have the same ...
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22 views

Reprojection not generating properly the tiles

I am executing this query with cartodb.js. I am moving the markers radomnly to generate a new layer. cartodb.createLayer(map, { user_name: 'mickemr', type: 'cartodb', sublayers: ...
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40 views

Postgis query on 3D cube does not use index

I am testing Postgis on the follow query: SELECT * FROM particles WHERE position &&& 'LINESTRING(0.08537 0.0738 0.0145,0.0953 0.0837 0.0345)'; that returns about 100k rows from a ...
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1answer
28 views

How to cut contour lines at the edge of a data source

I have calculated some contour-lines using gdal-contour for two elevation model into a Postgis database. One is high res and the other lower res. Now I am seeing problems at the edge of my high ...
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33 views

How to arrange polygon in Postgis

I have a lot of polygons in a Postgres database. I want to show the polygons, but in order of the the biggest to the smallest. I used the following code: SELECT ST_Area(area_polygon) as luas FROM ...
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46 views

Problem with spatial index PostGis

I'm using Postgis 2.1. I have this table with about 50k rows: CREATE TABLE rilevazioni ( geom geometry(Polygon), stimolo integer, tmstmp timestamp without time zone, id bigserial NOT NULL, ...
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57 views

Matching GPS points to the road network

I am a newbie in Postgres and Postgis and I am trying to do a matching of GPS points to the road network. I need to find closest road from a shapefile and take speed attribute from it. I am using ...
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3d vector and geometry operations in open-source GIS

There is some really good open-source software available to work with 2D vectors. For example QGIS has operations like buffer / clip / dissolve / select by location / join attributes by location... ...
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How to store a circle in PostGis database row [duplicate]

I'm using PostGis 2.1. I need to store different type of geometry like polygon 2D,polygon 3D and also circle. I need these polygons represent areas in which an event occurs. Then I'll have to do ...
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63 views

How to create line segments between pairs of pixels in a raster?

I want to draw several lines between pixels (please see the image below) according to some criteria : First Criterion: The distance between 2 pixels is less than 2000m and greater than 500m ...
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1answer
61 views

ST_Intersection for polygons

I'm looking for a query that returns overlapping areas of two tables with polygon geometries. Using row_number() over() the entries of the gid column are not unique in the case of dumped ...
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45 views

Find shortest path between two points without spatial database

I have an an certain area contains less than 200 roads(polylines), and I need to calculate a shortest path between two specified points inside the area. I know maybe I can use the pgroute in postgis ...
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35 views

Import OSM Notes dump into PostgreSQL?

I'm planning to write some software to improve handling of OSM Notes, so I need them in postgis database. Following the documentation I found there is notes dump on osm.org, but I can't find if ...
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65 views

Visualizing variability in the size and shape of polygons

I am working with a data set of area restrictions imposed by criminal courts. These restrictions ban a person from entering a demarcated area. These restrictions vary in their size, shape, and ...
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32 views

simplify tiled geometries while preserving anything on the edge

I have a dataset of polygons split into evenly sized tiles. How can I go about simplifying them, but not along the tile edges, so that there aren't any gaps between continuous features when the tiles ...
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43 views

Why is mapserver returning a blank image?

I am trying to load a layer from a postgis database, mapserver does not return anything. I think I have narrowed the problem down to the fact that the sql query mapserver is running is returning ...
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60 views

Determine XY offset in meters between two lat/long points (EPSG:4326), and accurately recreating point locations using XY offset

I have two tables in EPSG:4326, one for home locations and one for site locations. I need to be able to generate the XY offset in meters between the home location, and the site locations. I then need ...
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29 views

ArcGIS resampling rasters by maximum pixel value?

I need to resample a binary image of linear features like roads, rivers to a coarser resolution, conceptually combining multiple pixels into a single one. 1 indicates presence of the linear feature, ...
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33 views

Speeding up PostGIS ST_AsGeoJSON

I am writing a query that would give me the geojson element contains the outline of a US State along with some additional information. The problem I am running into is the function ST_AsGeoJSON from ...