Questions tagged [postgresql]
PostgreSQL is an open source object-relational database system.
515
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Finding the closest Geometry in PostGIS
I've been looking over the PostGIS "API" of functions, and I notice that most of them take two elements to compare. For example, the ST_Distance function takes two geometry/geography elements to find ...
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answer
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What is difference between ST_DWithin and ST_Distance for proximity search in PostGIS?
I have records stored in a table with latitude/longitude coordinates stored in a geometry field. I want to find all records nearby a user supplied reference point. Note "nearby" probably means less ...
- 1,233
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Multipoint vs point PostGIS
Is it normal to use the geometry type 'multipoint' instead of 'point' knowing that I use it to store only one point?
How can I convert from multipoint to point?
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How to perform a spatial join of point and polygon layers in PostGIS?
I have a point dataset representing households that I want to associate with a parcel layer (i.e. assign its parcel_id). With ArcMap, I could spatially join the polygons to the points and specify that ...
- 1,974
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ST_Union fails with TopologyException despite valid polygons and using ST_SnapToGrid
I am working with Postgres 9.6 and PostGIS 2.2.2. These are my tables:
Table "public.allparcels"
Column | Type | ...
- 3,299
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How to create linestrings with a definite angle and length, that are fixed to a point
I want to create linestrings with a definite angle (e.g. 160°) and length (e.g. 2m) that are fixed to a number of points of another linestring. So, I want to use the ST_DumpPoints function to find the ...
- 4,434
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10
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PostgreSQL Shapefile import failed
I am very new to PostGIS/PostgreSQL. In fact, I downloaded it because of the answers I got to this question: Distance between centroid and farthest point of polygon
I installed both PostgreSQL and ...
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What Spatial Reference System do I store Google Map's Lat/Lng in
I am new to PostGIS, Spatial Reference Systems and projections and want to store lat/lng coordinates retrieved from Google Maps and Openstreetmap and its services like the Geocoder/Nominatim. I'm ...
- 1,687
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4
answers
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Querying points inside and outside of polygons?
In PostGIS I have two tables:
Table that contains polygons:
table a.provinces
gid | geom | name |
------------------------------
1 | 010604 ... | Champagne |
Table that contains ...
- 441
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votes
1
answer
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Loading QGIS project from database using PyQGIS
I am trying to open a QGIS project that is saved to the database (Project -> Save to -> PostgreSQL) by means of Python script.
I find a similar way to open project which is saved to the desktop ...
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ArcMap error drawing postgis layer - The number of points is less than required for feature
I have one big polygon called huc and a multilinestring called streams, I am running an intersection on between the two layers to clip the streams to the huc.
here is what I have so far
drop table ...
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3
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Prevent export to shapefile from PostGIS table in QGIS
I have created a centralized database using PostgreSQL and created multiple users assigned with different roles i.e. SELECT, UPDATE, MODIFY and DELETE etc.
Example:
CREATE USER hasan WITH PASSWORD '...
- 1,606
6
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3
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Using ST_split to split a line feature using nearby points
I have a line shapefile and a point shapefile, and
the line has just one segment
and its attribute table,
the point shapefile has points near the line above, not on it
and the close look,
I want ...
- 1,555
5
votes
1
answer
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Editing PostgreSQL geodatabase table using ArcPy?
I'm trying to update a table using a python script and it's not working. The table resides in a postgres geodatabase and is versioned. I have also verified my user permissions (I'm the admin). The ...
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QgsDataSourceuRI and left outer join
I'm trying to load data from different tables using left outer joins into a QgsVectorLayer. The approach I'm following so far is the one from the developers cookbook here. The underlying database is ...
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