Questions tagged [postgresql]
PostgreSQL is an open source object-relational database system.
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What does the values in column clazz (osm2po) mean?
I have a given table in postgreSQL with OSM data which is used for routing purposes in Java with PGRouting. There exist two columns which I don't understand. They belong to osm2po. They are labeled ...
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Take from multilinestring the start and end points
I have to use the A* algorithm and my geometry is in multilinestring and I want to take stratpoint(x1,y1) and endpoint(x2,y2) .
I use this queries but the columns after the execute is still empty
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ST_LineMerge to simplify road network
I am trying to simplify my road network by finding all segments that touch 2 other lines with a common attribute, join_id and street, then doing a st_linemerge. I do NOT want to merge lines where ...
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PostGIS - Linestring doesn't contain a Point - Problem
I have a problem to check if a Linestring contains a Point.
I consider the straight line y = 0.1 x , and take by it a segment l='Linestring( 0 0 , 4 0.4 )' and a Point p on segment l, p = 'Point(1.5 ...
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Error editing 'editable' view in QGIS
Taking some code from this post, I've been trying to create an 'editable' view in PostGIS.
I'd like to store label placement properties in a separate table, build a view of the data I want to use for ...
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Writeogr to PostgreSQL/PostGIS database with R
I'm producing some Spatialpolygondataframes with R that I would like to upload to my PostGIS Database. I've found out that the way to do this is via the writeOGR() function using the PostgreSQL driver....
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Clip overlapping polygon in equal sharing size
Within single shapefile I am trying to clip overlapping polygons to their boundaries using centre line of overlapped area using Postgis or ogr2ogr.
I tried to use ogr2ogr command to remove slivers
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How to run a moving window function in a conditional statement in PostGIS for buffer artifact removing?
I try to remove the artifacts which occur when running the ST_Buffer function in PostGIS PostGIS 2.5.1 (See picture). For this case I wrote a function that should loop trough every segment (row) and ...
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Searching planet_osm_point by longitude and latitude
I used osm2pgsql to import data into my PostgreSQL database and it put gave me the following 4 tables, planet_osm_point, planet_osm_line, planet_osm_polygon and planet_osm_roads.
I have looked at ...
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From QGIS 3.4.5 and 3.6 asks password repeadly to connect to PostgreSQL 10 [closed]
Action: At first time when opening project on QGIS 3.4.5 and 3.6 versions needs credentials to connect to PostgreSQL DB.
Problem: But after that when connection is success with correct credentials ...
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PostGIS combine ST_DistanceSphere with Nearest Neighbor search
I have two tables both have point geometry with SRID 4326 (WGS84)
I need to find the nearest point in 1 table to every point in another table
PostGIS KNN search is written
t1.geometry <-> t2....
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Speedup function to calculate distance from centroid of building to river segment in PostgreSQL
I am trying to measure the distance from the centroid of a building to a river segment using the following function.
CREATE OR REPLACE FUNCTION river_foo_mapper () RETURNS trigger LANGUAGE plpgsql AS ...
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How to install PostgreSQL 9.2 with PostGIS 2.0 on Ubuntu 11.10 (or higher)?
I have read this question: https://dba.stackexchange.com/questions/25033/install-postgis-v2-for-postgresql-v9-2, but it didn't resolve my problem.
I added the PostgreSQL backports PPA and installed ...
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ST_Distance does not give nearest node
I am trying to find the nearest point on the road network closest to a given point. I imported the road network into PostGIS from QGIS and am using the SQL window in QGIS DB Manager to query the road ...
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How to snap points to line
I am having a table lines being MULTILINESTRING (2 Dimensions) and a table points being MULTIPOINT (3 Dimensions). The two are in the same CRS.
Now, I am trying to snap all the points to the closest ...
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