1
vote
1answer
30 views

Postgis create polygon extent/convex hull from spatial table

Please help, I have a polygon layer representing building footprints. I want to create new view in postgis that will contain rectangle representing bounding box and also another view that will have ...
1
vote
1answer
41 views

SQL-query should return GeoJSON FeatureCollection

I'm trying to return a GeoJSON FeatureCollection object from a SQL-query with PostgreSQL 9.3 and PostGIS 2.1. This is my query so far: SELECT row_to_json(fc) AS p FROM (SELECT 'FeatureCollection' ...
0
votes
0answers
19 views

time complexity of selected algorithm - SQL

I use PostGIS - SQL 1) I need know time complexity of algorithm which in I use these functions: ST_Equals, ST_Overlaps, ST_Distance_Spheroid and ST_Dwithin Is a time complexity diferent when I use ...
1
vote
1answer
63 views

PostgreSQL/PostGIS: create spatial view

I have a polygon layer and a point layer. 1) I wrote a spatial query to count how many points fall in each polygon: SELECT polR.codeR, count(pntAZ.geom) as tot_pntAZ FROM boundaryR as polR LEFT ...
0
votes
1answer
31 views

I need to test a condition within the sql in postgis.

I need to test a condition within the sql in postgis. My sql: SELECT (zoneamento3_32722.zt3), logradouros32722."NMIDEABR", logradouros32722."OBJECTID", ...
0
votes
2answers
37 views

How to join data in postgis tables to form layer with subset of attributes

In QGIS I am trying to join data from two postgis tables. I can not figure out how to do this at sql because add layer tools seem to allow one to select just one table to filter on. Instead I ...
0
votes
0answers
27 views

Postgresql (soln would be basic SQL I think): ORDER by distance to a point and return those distances in array pairs w/ the full records

so I know there have been some questions asked about how to calculate distance using postgis and how to order results by their distance from a respective point. I'm not very talented at SQL (at all) ...
0
votes
1answer
21 views

PGrouting encapsulated queries error [quotes problem]

I'm facing a quote problem on a pgrouting query. What I'm thinking is wrong is that my query only works if I use one, then four, then eight quotes on encapsulated queries. Is there a way to simplify ...
1
vote
2answers
65 views

adding geometries to a source, target table for multiple rows in pgrouting

I am having an issue trying to perform the pgr_dijkstra algorithm and getting back a line in my table for multiple rows. I have a table that has a columns of source, target node id's but I cannot ...
2
votes
2answers
80 views

How to get the data type of each column from a postgis table

I need to get the column data types of all columns in a table, including the geometry types. What I wanted to know is if there is a function or SQL that gives something like this: column_name | ...
1
vote
0answers
73 views

PyQGIS Dialog Plugin not resetting

I have written a PostGIS search plugin that works pretty well, except two things that I just cannot figure out a solution 1) When the dialog closes and then is reopened the previous query is still in ...
0
votes
2answers
32 views

How can I optimize this point-linking query?

I have the following query, and am wondering how it could be optimised to run faster: WITH gps_nodes_1 AS ( SELECT "NODE_ID", "geog" FROM gps_nodes WHERE ST_Distance("geog",ST_GeogFromText('POINT( ...
0
votes
1answer
35 views

How can I combine two datasets with the same schema in to one table?

So I have two tables (in CartoDB/PostGIS) that are from two tiger shapefiles that have the exact same attributes, just in different counties. I want to combine them in to a single table, just ...
0
votes
2answers
51 views

sql query to get origins and destinations

I have a table of cities with an ID and geometry (200K rows) and a table of travels, with only two ID: idfrom, idto (7K rows) I'm wondering how could I select the geometries for each one in order to ...
1
vote
2answers
94 views

How can I create a hexbin layer using the SQL and CartoCSS parameters in cartodb.js?

CartoDB has a great hexbin visualization wizard baked into the client dashboard: However, I like using cartodb.js to customize events and interactions; in particular, I'd like to make styles ...
-1
votes
1answer
132 views

Shortest Path Dijkstra

I would like to calculate the shortest path with dijkstra algorithm. sample query SELECT seq, id1 AS node, id2 AS edge, cost FROM pgr_dijkstra(' SELECT gid AS id, ...
0
votes
1answer
80 views

How to cut/split multipolygon with blade (linestring) into two pieces using PostGIS? [closed]

I struggle to do split operation in postgis I tried to build a query but Im always fail. Id like to cut a multipoligon with a blade (a linestring) into two pieces. These two objects have specific ...
1
vote
1answer
42 views

Rewrite query to match two points with a linestring in a different database table

OK, not sure if I've worded the title brilliantly, but here goes: Suppose I have: a table "gps_nodes" containing columns: "EASTING" (containing longitude data) "NORTHING" (containing latitude ...
3
votes
1answer
322 views

PostGIS intersection function

I have a problem with intersection function. I built my query following http://manual.linfiniti.com/en/postgis/geometry.html, 5.7 section. I made my clip object, a red linestring frame: But after ...
1
vote
1answer
94 views

Calculating difference between bearing values in degrees

Suppose I have 3 geographic points, A, B and C. I can calculate the bearing of B from A (in degrees) using this SQL snippet: degrees(ST_Azimuth(geogA,geogB)) as brg_a_b ...and the same of C from ...
4
votes
2answers
422 views

SQL Syntax to extract (convert) Strings with Degrees Minutes to Decimal Degrees

I have a PostgreSQL/PostGIS database with a two string fields containing Lat and Long coordinates in degrees and decimal minutes, like this 45° 24.5' N 3° 43.01' E. How can I convert them into ...
3
votes
1answer
56 views

Use selected value in postgis function

How can I use the selected value from a SELECT statement in a PostGIS function. e.g. using the geom_way from SELECT geom_way FROM osm_2po_4pgr ORDER BY ST_Distance(ST_GeomFromText('POINT(21.323329 ...
4
votes
2answers
632 views

Import large CSV file into PostGIS

I am trying to import CSV files into PostGIS. Following this post, I have created tables before. I found other suggestions saying that I can run the copy command. If I run this command: COPY table ...
1
vote
1answer
188 views

Trouble with INSERT in PostgreSQL 9.1

I am trying to execute the following: INSERT INTO lithic (cp_east, cp_north, type, material, art_count, comment, field_no, gps_unit, initials, rec_date, cortex, geom) SELECT (cp_east, cp_north, ...
2
votes
2answers
79 views

shp2pgsql mangles date field — quotes data as if it were char or varchar

I'm attempting to import a shapefile into postgis via shp2pgsql. Among the fields in the shapefile's .dbf file is a date field with format yyyymmdd, which is a valid date format for postgresql. ...
0
votes
1answer
47 views

Issues with pgrouting workshop code in postgis 2.11/pgrouting 2.0

I'm having issues getting the pgrouting workshop to work on Postgresql 9.2/PostGIS 2.11 and pgrouting 2.0 on windows. How can I rewrite the following php/sql code and make it compatible with my ...
0
votes
1answer
551 views

Postgresql Trigger to insert records in my table from another one

I spent few days trying to resolve this question but it was impossible. I have two tables: Table1. CREATE TABLE point ( id_point integer NOT NULL DEFAULT, layer text, elevation numeric, ...
0
votes
1answer
287 views

Postgis: find geometry within multiple polygons

I've got two tables with geometry in it. Table 1:items holds items with a point geometry; while the second table property_zones holds polygons. The Items: CREATE TABLE public.items ( id integer ...
2
votes
1answer
89 views

How to split polygons with another polygon and inheritage data?

Let's say that we have two tables with polygons representing areas. Table A and Table B. Geometries from table A represents both the valid and invalid areas. And the geometries in table B represents ...
2
votes
1answer
79 views

Tiger geocoder / postgis - get county from point

Looking for some help with getting the county for a lat / lon. I have postgis / tiger geocoder installed and can reverse look up a point and get the addresses. I would like to get the county the ...
1
vote
1answer
113 views

Three table postgres sql join query

I'm having trouble getting my SQL query to work with three tables. I'm new to SQL to I've already spent considerable time trying to understand the documentation and making some sense of it. I'm using ...
1
vote
0answers
52 views

How do I make vectorlayer with sql on PostGis via python code

I need to make a vectorLayer and fill with the SQL's results on PostGIS via python code. I'm working with python 2.7, QGIS 1.8 and PyQt 4.5 How do I it ? thanks
2
votes
0answers
55 views

What is the MS SQL Spatial syntax for counting points within polygons? [duplicate]

All, What I'm trying to do is this: Count points within polygons There are thousands of points and maybe 2 dozen polygons Get a list back of the 2 dozen polygons by name and the count of points ...
1
vote
2answers
811 views

How to select all points within a circle in PostGIS?

I have set of points in a PostGIS Table (Type Geometry). Now, I need to filter points that lie in a circle with a center (C) and radius (R)! I expect C to be of type Point or Coordinates.. R to be ...
1
vote
2answers
556 views

How to connect Dotspatial with PostGIS/PosgresSQL database and perform SQL function

I am currently doing a project that needs a GIS front-end interface to visualize geographical objects (road networks), and a back-end geo-spatial database to implement network analysis (SQL based). ...
2
votes
1answer
238 views

How to merge connected lines with same direction (PostGis)

I am looking for a way to join all lines that are connected, have the same direction, i.e. start point of one is end point of the other, and share some common attributes. In fact, I want to connect ...
6
votes
2answers
590 views

What are benefits of using ArcGIS with PostgreSQL over simply ArcSDE?

I understand that in order to benefit from ArcGIS spatial datatypes (ST_GEOMETRY, versioned geodatabases etc.) ArcSDE needs to be installed - and with the 10.1 client it is automatically installed ...
2
votes
1answer
529 views

How to get polygons from PostGIS table to PHP array best?

Currently I fetch polygons from a database table using ST_AsText(). The results are in text format, like the following. POLYGON((84 104,212 48,321 122,243 179,275 238,131 240,84 104)) I am not ...
0
votes
2answers
862 views

Cannot insert simple geometry data

I installed PostgreSQL 9.2.4 and PostGIS 2.0.3 on my Windows 8 machine. Then I created a table using phpPgAdmin and added a geometry column using the following statement. SELECT ...
1
vote
0answers
364 views

PostGIS Better ST_Intersects Query

I am currently using the following queries to return all features that intersect a large and complex polygon. I initially tried to use a single ST_Intersect query but because the number of features it ...
2
votes
1answer
183 views

SQL Command to convert pgRouting result to GeoJSON

My goal is to produce a Web UI for pgRouting using this tutorial. I have already imported my data from an OSM pBF to PostGIS using osm2po. Using the pgRoutingLayer plugin for QGIS, I was able to ...
0
votes
1answer
327 views

ST_Box2D in PostGIS 2.0

I am getting an error trying to create a bounding box of a geometry using ST_Box2D(). Is the function deprecated? If so, what is the equivalent function? SELECT ST_Box2D(ST_GeomFromText('LINESTRING(1 ...
1
vote
2answers
321 views

Function for Selecting Points in a Polygon

I've been banging on this for a few hours, but since I'm relatively new to PostgreSQL and PostGIS, I can't find the solution. I'm trying to create a stored procedure (function) which will return all ...
3
votes
1answer
185 views

Given a lat/long point, determine if it's land or water?

I have a PostGIS-enabled PostgreSQL 9.1 installation with the 10M physical dataset from Natural Earth imported. It's been converted to 900913, and in QGIS I can visualize the data. So the plumbing's ...
3
votes
2answers
153 views

Traversing a PostGIS table tree

I'm developing a geospatial db for a company that operates at a number of large facilities. Its primary purpose is to help staff locate themselves and equipment within each facilities' multi-storey ...
4
votes
2answers
318 views

PostGIS stored procedures

I am wondering if there are open source applications that make extensive uses of the special functions (the ST_* stored procedures) provided by PostGIS? I found many apps that support storing map data ...
1
vote
1answer
81 views

How to get routes in the database that intersects circle?

I have routes (linestrings) recorded in the database. I want to create a query which returns the routes that have some commonality with a circle whose center and radius are passed as parameter. I ...
3
votes
1answer
498 views

Routing with multiple points

I am using postgreSQL, postGIS and pgrouting. Now I am really confused on how am I going to find the shortest path between multiple points. I know how to find it between two points through dijkstra ...
6
votes
2answers
935 views

PostGIS SQL query to find a polygon that intersects with a line

I need to build a PostGIS query that would select every polygon inside an area the river is flowing through. I'd better describe with an example below: There is a river (blue line) flowing through ...
1
vote
1answer
159 views

What are FLOOR and CEILIING in PostGIS designated for?

Just a short question to lighten up my understanding of some PostGIS-code: Regarding the creation of user-defined grids I often find the expressions CEILING and FLOOR. Like in this non-representative ...