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

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5answers
468 views

What in-depth spatial database systems tutorials exist?

Is there a good tutorial that explains in depth the internals of a GIS and a spatial database system such as PostGIS with examples and without any background assumption? I'm specifically looking for ...
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1answer
203 views

Is the GIS Repository In Ubuntu in a different stream than the main repository?

I was checking out this: https://wiki.ubuntu.com/UbuntuGIS and it outlines how to install PPA for GIS. I performed a basic apt-cache search on a few things and QGis and mapserver are available. Such ...
1
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1answer
563 views

Is it possible to use Leaflet, PostGIS and PGRouting for web mapping?

I am newbie at Open Source GIS. I have already create a web mapping using custom tiles and leaflet. I have used my my own database. Tilemill was used to create the tiles and leaflet was used to ...
1
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1answer
116 views

caching part of a postgis layer in mapserver

I'm creating a layer in mapserver using postgis. The layer consists of many polygons. Sometimes some of those polygons will change. Is it possible to cache the layer tiles using something like ...
4
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1answer
762 views

Update a newly added column of a table using ST_Intersection as a filter

I would be really grateful to anyone that could help me with the following issue. I have ever used PostGIS much before - so could be considered a newbie... My Situation: I have TWO PostGIS tables: ...
6
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1answer
135 views

Should the geometry column always be the last column of a postgis table?

When we need to add an attribute to a table (e.g. a table of 350,000 polygons), my instinct is to always recreate the table so that the geometry column is last. I think this is a best practice for ...
5
votes
4answers
536 views

How to build PostGIS database schema for flexibility and normalization?

I'm creating a database that will be used by researchers in population genetics with different goals and sampling strategies. The database needs to accommodate locations as points, lines, or polygons ...
2
votes
4answers
1k views

Query Postgis Table with PHP

Would you be so kind as to help me with the following in OpenLayers. I need to be able to use the coordinates from a user click in a postgis query. To catch the coordinates of a click I built a click ...
13
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2answers
5k views

Postgres/Postgis spatial index - no speed up

I have a spatial table in a postgres/postgis database. Every row in it represents a Polygon. It is of following form: +----+--------+ |gid | way | +----+--------+ |241 | 01030..| The geometric ...
7
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1answer
2k views

What is a “non-noded intersection”?

Can someone provide a precise definition of what a "non-noded intersection" is? There are various GIS platforms and toolkits that have errors with this text, and Google search results for this tend to ...
2
votes
2answers
409 views

Why does GeoServer copy my PostGIS tables?

I have some geospatial data in a PostGIS database. I want to serve that data to a web map app with GeoServer. But every time I add a table as a layer in GeoServer, it creates a duplicate table in ...
4
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4answers
1k views

Create a point x meters from origin using st_translate in postgis

How do I create a point 1000 meters away from a reference point? The ST_Translate only supports geometry type. I also tried using ST_GeomFromText but that returns a unit and not in meters. Here is ...
3
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1answer
958 views

Dynamic SLD styling - unique colours for linestrings

I have a postGIS table that looks like this: (plus a 'track' geometry column, a linestring for the vessel's track) sampling_interval | voyage_name | start_time_utc | id | ship_name | ...
5
votes
1answer
952 views

Why isn't StackBuilder installation of PostGIS working?

I've installed PostGIS (ver. 2.0.1) on my Mac using EnterpriseDB's StackBuilder, which I also used for my PostgreSQL (9.2.2) installation. Although StackBuilder says that PostGIS is now installed, and ...
1
vote
1answer
647 views

Broken image from mapserver, png not rendering

I'm trying to render WMS MapServer data on top of Google Maps using the OpenLayers JS library. My problem arises when I try to render the data as a series of points throughout the New York City area. ...
0
votes
1answer
657 views

Column exists in DatabaseMetaData, but does not exist in relation?

I am using JDBC to query a PostgreSQL database. And I want to populate a column called wiki_url based on the value of another column, level which will determine which value of 5 columns to concatenate ...
2
votes
2answers
1k views

How to project a geoJSON file in OpenLayers?

I have a json file well formed. I want to read a json file as a base layer from OpenLayers. <script type="text/javascript"> var styles = new OpenLayers.StyleMap({ "...
0
votes
2answers
920 views

Error import ShapeFile shp2pgsql-gui

I'm trying to import a shape file to my PostGIS database but I can not, give a look: Importing with configuration: 12mie250gc_sir, public, geom, / home/samuelribeiro/Desktop/MALHA_DIGITAL/ac/...
12
votes
2answers
918 views

PostGIS interpolation / triangulation options

I'm looking for an open source workflow to automate DEM construction. We have a series of sites that fall within a LIDAR dataset. We want to create site specific DEM's for each site, and we're ...
2
votes
1answer
682 views

Why does Geoserver not serve my primary key/ id?

I have a postgres/postgis table with the columns: gid [PK] serial NOT NULL, geom geometry(MultiPolygon,900913), crop text My layer in Geoserver however only shows me the feature types "geom" and "...
2
votes
1answer
703 views

How to bulk delete shapefile columns?

I have shape-file with next attribute table: - name of features, unique number for each feature of layer I must split shape-file by NAME field, but in result in attribute tables of layers should be ...
4
votes
2answers
241 views

Where can I find the freeware ST-Links PgMap?

I am trying to connect to a PostGIS database from ArcGIS Desktop 9.3.1 Some web-searching suggested that zigGIS would be useful. Unfortunately zigGIS has reached the end of life, and the author of ...
2
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1answer
462 views

Convert native box to geometry

I have an old table that contains bounding boxes of lat long coordinates in a "box" type. How do I convert them to PostGIS geometry ? I tried using ST_Transform(ST_SetSRID(se.bound_box::box2d::...
1
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0answers
135 views

GeoServer and PostGIS connection technology

Does anybody know how GeoServer connects to PostGIS. Which technology is used? Is it JDBC? Thanks
3
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1answer
2k views

Merging multipolygon data into a polygon

I have a MultiPolygon representation of some shapes in POSTGIS, I am trying to convert them to Polygon data. I tried, st_geometryn(r.geom, 1) but that didnt work because the way polygons are ...
2
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0answers
1k views

How to handle postgresql/postgis geometry type errors in a function?

I have created the following function in PL/SQL to make a polygon from a set of linestrings: CREATE OR REPLACE FUNCTION _myfunction( _fid integer, _rid integer ) RETURNS VOID AS $$ ...
1
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2answers
589 views

Polygon intersection with bounding box with polygon's holes intact

I am trying to serve GeoJSON FeatureCollection tiles with each feature's geometries trimmed to the tile boundary. I am working on a Leaflet plugin to re-assemble the geometries. It works by building ...
3
votes
2answers
234 views

In Postgis 1.5, how can I split lines in points while retaining the id?

Hypothesis: Having 2 linestring tables: pipelines (id integer, street varchar(50), shape geometry) streets (id integer, name varchar(50), shape geometry) Each pipeline passes/intersects several ...
2
votes
0answers
200 views

Projecting PostGIS in Openlayers

I have a layer(base layer) with MultiLineString Geometries and now I need to project the layers(overlays) in the base layer from PostGIS using OpenLayers. However, I got an idea how to project table ...
1
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0answers
29 views

How to perform a join on simultaneous spatial and attribute criteria in PostGIS [duplicate]

Possible Duplicate: How to perform a join on simultaneous spatial and attribute criteria in ArcGIS? I have two point layers and want to perform a spatial join on nearest distance. I have a ...
2
votes
0answers
58 views

Is it possible to permanently save the Edit Widget for a Postgis layer?

Is there a way of configure the editing type for a POSTGIS layer through Edit Plugin and do not lose the changes after remove the layer or exit the program?
0
votes
1answer
186 views

Trigger on link length and filling attribute table

I create linear geometry in QGIS 1.8.0 (geometry stored in PostGIS 2.0). Help create trigger functions: in database should not be a lines less than 2 meters (linear geometry with length <2 meters ...
4
votes
2answers
2k views

postgis error: when adding features geometry has z dimension but column does not

I have to define a geometry column in PostGIS for 2D points, but when I try to import points from DXF to postgres I get the following message: "postgis error: when adding features geometry has z ...
8
votes
4answers
2k views

What is the best web editor and server for postgis?

I'm looking for a web editor (similar to openstreetmap) that works with an map Server (postGIS). This should permit edit and create new structures on map. What is the best option? Can you help me? ...
2
votes
1answer
451 views

How to return nearest point to input lat/long with distance?

I am trying to write a query with PostGIS that returns one row where the geometry of that row is the closest to an input point. I would also like to include the distance between these points in the ...
2
votes
3answers
789 views

How does ST_Azimuth work?

I do not understand the function behaviour. I am giving the function a point B that is North of point A so I would expect something around 90 degrees but I get 263 degrees instead. In another example, ...
6
votes
2answers
4k views

PostGIS ERROR: could not load library “/usr/lib/postgresql91/lib64/postgis-2.0.so”

OS is openSUSE 12.1, PostgreSQL - 9.1, PostGIS - 2.0. Postgre/PostGIS are installed from Application:Geo repository. After recent updates when I try to connect to my database I get the following ...
4
votes
4answers
890 views

Caching / Preloading data for use with WMS queries

Hoping someone can help me with this issue. I've got a map implemented in my web application using OpenLayers that makes WMS queries to GeoServer that in turn queries a Postgres (PostGIS) database to ...
6
votes
2answers
232 views

How to sample a 3D raster along a 3D path (or 4D raster along 4D path)?

I have a 3d raster dataset of atmospheric variables (lat x lon x altitude). I would like to sample this raster dataset along a 3d path. Any idea how I can achieve this, preferable with qgis or ...
3
votes
1answer
88 views

PostGIS - improving sql statement

I've managed to create the below statement that creates a table based on a point in polygon query. However it creates a column that gives a true/false value which I then delete out all the f values ...
11
votes
2answers
899 views

Are there any tricks to using a schema other than public in PostGIS?

I'm currently setting up a fresh install of PostGIS 2.0.2 and PostgreSQL 9.1.6 on Ubuntu. I've recently come across some information indicating that using the public schema to store all data is not a ...
3
votes
1answer
222 views

Creating a vector based design from a raster database

I have a raster table that I've created using Postgis raster. It has 365 records and the table looks like this: +-----+------------+---------+------------+ | rid | rast |filename |date_of data| ...
2
votes
1answer
4k views

SRID 4326 and geometry conversion

From this line: SELECT ST_AsEWKT(geom) FROM buildings LIMIT 1; I get this result: "SRID=4326;MULTIPOLYGON(((404269.308014269 4543087.6184561,...)))" I'm wondering if the coordinations are ...
3
votes
1answer
5k views

How to fix incorrect SRID of the geometry column? [duplicate]

I've been told to use AddGeometryColumn to properly add a column with correct/preferred SRID. however I wonder if it's possible to fix/change the current column instead of adding a new? If there's no ...
1
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1answer
312 views

Why does Find_SRID return zero?

using SELECT Find_SRID('public', 'myTable', 'myColumn'); I get zero as the result, what does it mean? Regards,
11
votes
3answers
2k views

How to speed up queries for raster databases?

I have a raster database in postgresql/postgis with these columns: (ID, rast, data_of_data). 'rast' is the column that has raster files in WKT format. An example query to find the DN value of a ...
3
votes
3answers
906 views

How to find SRID for random polygon?

I'm testing spatial database performance on a dataset. Spatial objects in this dataset (stored as WKT in a flat text file) are random valid polygons which have vertex coordinates (x,y) where 100,000> ...
1
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1answer
457 views

loading multiple shapefiles using shp2pgsql in a bash script

I have this bash script (loadShapefiles.sh) to load multiple shapefiles at a time. The script and the shapefiles are stored in the same directory. When I run the bash file with the command of bash ...
0
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0answers
173 views

Can I do full SQL expressions through the “WHERE” clause in UpdateCursor?

Run as a standalone python script for a shapefile in a toolbox on ArcMap. For example: psql_url_pop = '''SELECT shapefile.NAME_# + shapefile.WIKI_URL FROM public.shapefile''' rows = arcpy....
1
vote
2answers
936 views

dealing with 2 different coordination systems in postGIS

I'm seeking a function that converts degrees to the following format: POINT(405115.926025391 4543389.4354248) I dont know this format's name, but is there any function to do so? Cheers, EDIT -----...