Acronym for Structured Query Language. A syntax for retrieving and manipulating data from a relational database.

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How to populate data from postgresql using dynamic php\html listing

In the form I created, I need two fields to be dynamically populated from the database while the other fields will be manually entered and push to the database. I have written a script that is able ...
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213 views

run sql on Qgis

I want to do simple demo to our manager with quantum gis. i have buildings from my city with wgs84 projection on postgre sql database and also have non gis table which have who leaves this buildings (...
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Database has duplicate values after running pgrouting

I am a newbie with postgresql and sql statements so maybe it is a trivial question, I'm sorry for that. I am working on a postgis database and try to use the pgrouting function. My goal is to store ...
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153 views

Proximity query approach

Let's say that I have two tables in PostGIS, tracks and cities, each table has two columns, in both cases the columns are called name and way, name is a string, way is a geometry. I want to retrieve ...
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328 views

Cordenadas 2d transformacion a postgis desde QGIS

This is a three-dimensional shape file, I checked in ARCGIS, where the shape attribute indicates POINT ZM, This is the table fid 0 shape* point ZM atribut1 A atribut2 B ESTE ...
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How to offset point perpendicular to line direction in PostGIS

I have a postgis table of points, that are sitting on road centerlines (I've linear referenced them). And the second table with road centerlines themselves. The point table also has a field roadid and ...
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How to Calculate length of polyline geometry for several tables in PostGIS?

PostGIS database contains several geometry (polyline) tables (with names "D1_r", "D2_r", "D3_r"). I calculate length for one "postgis layer" use request: SELECT sum(ST_Length_Spheroid(the_geom,'...
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688 views

How to create a point table from a remote csv file?

The current approach that I am using to load a csv file into a PostGIS enabled database on a server is the following: -- create table CREATE TABLE points( id int, lat double precision, lng double ...
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Acquiring ArcGIS-like speed in Postgis

I have been using Postgis 2.0 for 3/4 of a year now and while I really enjoy using it, excessive query processing time has rendered it basically unusable for my use case. I tend to do heavy ...
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How to interpolate GPS Positions in PostGIS

I have a PostGIS table of GPS positions for every five seconds: 2011-01-01 00:00:05, POINT(x1,y1) 2011-01-01 00:00:10, POINT(x2,y2) 2011-01-01 00:00:15, POINT(x3,y3) ... I'm looking for a query ...
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How to find loops in a network

I am a new in this field and need help, how to code using SQL spatial a function that retrieve loops in a network.The input, flag: Geography and barrier: Geography and two spatial tables, first ...
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776 views

How to select multiple features using advanced search SQL in QGIS

I have a layer of planning units covering a large area (there are over 16000 PU's). Three of the columns in the attribute table hold information about which planning units were included in the ...
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How to label features in QGIS using SQL statement?

In QGIS, I can't seem to find a way to define the features that I want to label using a SQL query? Is this possible? For example, I downloaded the OSM Natural shapefiles, and a lot of those features ...
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217 views

Postgis nested query trouble

I am having difficulty writing a nested postgis query. I have a single table from which I need to create a view in PostgreSQL. I have created the view with the following command create view rrop08....
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1answer
3k views

Performing Geoprocessing SQL Queries in QGIS from a PostGIS Database

This may be a dumb question, but is there way to run a PostGIS geoprocessing SQL query in QGIS? Specifically, I am thinking of running SQLs such as ST_Union, ST_Split etc etc. I have tried the ...
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600 views

Shorter Version of this SpatiaLite Query

I've been doing some spatial queries using spatialite, and they're large enough that a spatial index becomes a must. An example of using an index is given in the tutorial spatialite> SELECT ...
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Performance Gain Through GIST Index for Point in Polygon Query

I have two tables: locations(id,region_id,the_geom) and regions(id,the_geom). For each location point I want to determine the region it is located in: UPDATE locations SET region_id = (SELECT id ...
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ogrinfo SQL GROUP BY Clause

Does ogrinfo support a GROUP BY clauses? I could not find any good documentation of all the SQL syntax features it supports. I tried the following: ogrinfo . -geom=no -sql 'SELECT lsad FROM ...
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1answer
342 views

How to update attribute values of points outside an area?

I have two datasets in PostGIS 1.5 (on Postgres 9.1) one of polygons and one of points. I am hoping to create a SQL command that will select all of the points in a dataset that are not within of the ...
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635 views

Passing parameters to PostGIS SQL queries in Python: weird behaviour

The following code always goes to the except section and I do not understand why..Any help would be much appreciated. l = None c = conn.cursor() try: s = "SELECT ST_NPoints(ST_GeomFromText(%s))" ...
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1answer
442 views

SQLServer generating invalid WKT

I am a GIS novice using SQL 2008, with C# and the NetTopologySuite WKTReader type to work with some geometries. I have some data which I have been able to save into the database but when I read back ...
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147 views

Acceptable Reduce() amounts for google maps zoom levels?

I'm using SQL Server Spatial to return large polygons to Google Maps for display. Given that google maps has a zoom scale of 1 - 20, I would like to reduce my polygons (reduce function uses the ...
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Select points within a relative number range

I need to select points that have attributes that are within a relative number range of each other. For instance; given the following numbers: 95,705,139,65,537,266,525 and 188; I need to find all of ...
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1answer
2k views

ESRI File Geodatabase - Trying to use CURRENT TIME in Definition Query

Is it me, or are the date functions in the file geodatabase a total nightmare. Anyway, I am trying to set up a fairly simple definition query that contains a subquery with a date comparison. My ...
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365 views

Add building height from xyz points in PostGIS

I have been trying to get this query right and just can' seem to. I have a building polygon table with over 7 million polygons, indexed I then have a grided height XYZ table with attribute 'height' ...
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147 views

Postgis reorder mixed up linestring chunks / max_segment_length(linestring)?

I imported ~1000 paths from somewhere into my postgis database to a linestring field. I had the problem that the paths were divided into chunks, and those chunks were mixed up in some cases. Suppose ...
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195 views

SQL Plus error using sdeversion

I'm new to SQL Plus and I have a question. I've created several versions of a feature class located on a SDE database. I want to use ArcSDE Administration Commands found here but I'm getting an error ...
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1answer
112 views

Read height data from Meridian 2

I'm having difficulties reading the Gridded height data (OS Meridian 2). I'm loading with OSGB 1936 reference system but have trouble finding the lat/lon data for each point. i.e.I open the attribute ...
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Changing Buffer table geometry dynamically in PostGIS using plain SQL

I have two tables in PostGIS, a point and a point_buffer table. The point table has a buffer_distance field, with a default value say 200. Now I want to change the buffer table geometry whenever I ...
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314 views

Manifold 'Link drawing to query' - can I do this in QGIS?

Manifold GIS allows the creation of dynamic drawings linked to queries. Unfortunately I do not have access to Manifold as my employer refuses to pay for it, so am currently investigating alternatives....
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POSTGIS query of point feature. How to find nearest point to query location?

I am querying a point feature using a POSTGIS request fired in Javascript. The decoded URL looks like this and returns great results for polygon features. http://test.tablelocation.com/api/v1/sql/?q=...
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224 views

Running database operations against a stored GIS geometry

I'm using Quantum GIS and Postgres with the GIS extensions to store shapefiles that I'd like to run point in geometry and point in union geometries against. While it's easy to save and load the vector ...
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postgis minimum distance among many points [duplicate]

Possible Duplicate: Nearest Neighbor calculation in PostGIS Is there a way to achieve the following: SELECT ST_AsText(a.geometry), min(ST_Distance(ST_GeomFromText('POINT(10 20)'), a.geometry))...
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Selecting points not snapped

I have a point layer and a polyline layer. I want to select all points in the point layer that are not snapped to a vertex in the polyline layer. How can I accomplish this? I'm using MapInfo and ...
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What is the best approach to using IQueryFilter.WhereClause in ArcObjects?

What is your preferred / best approach to using IQueryFilter.WhereClause statements in ArcObjects (e.g. when selecting features by attributes)? You need to check the source type (shapefile / personal ...
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386 views

How to correctly use cursor.execute() with PostGIS?

I do not understand how the operator works some times... Here is an example that works, "SELECT ST_Distance(ST_GeomFromText('POINT(-3.16496271127842 55.9262620593642)'),ST_GeomFromWKB(a.geometry)),...
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How to fix pgRouting error “starting vertex not found”?

I've posted on here before about my battles with drivetime polygons and got some sensible suggestions back, so having Googled myself stupid over this I'm turning to you once again in the hope of a ...
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1answer
2k views

Good place to get Country, State, City, and Zipcode information?

I'd like to populate a database with common location information. I'm not entirely certain that addresses across the globe have similar or even the same entities as the Country, State, City, and ...
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763 views

ArcGIS Select Analysis using Unique Values from Field

I am trying to create separate shapefile using Select analysis with ArcPy by doing an SQL query to create them based on a unique value from the field. I want to create a list of the unique values in ...
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1answer
101 views

How to query distict row with the same label from different linestring with multiple segment?

I have a multilinestring street table in postgis with two columns: label and prefix. This table has 2 different roads with the same name and each road contains multiple segments. Roads were splitted ...
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261 views

ArcSDE recently modified geometries

ArcSDE 10 with a MS SQL 2005 backend. I am trying to see the most recently modified geometries using SQL so that I can use it to update another GIS database running PostGIS. Has anyone tried this ...
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Correct SQL statement in FME?

I am trying to write SQL statement in WHERE Clause FME in Navigator but it does not work. WHERE Clause: NAME IN SELECT CONCAT(''$(',SELECT REPLACE ('Roman Ann Jack',' ',','),')'') This sql code ...
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How to write a SQL WHERE Clause using Multiple Choice values in FME?

I published a parameter which is of Choice Multiple type. I wish to use values from this parameter for WHERE Clause when Reading Inputed Data in the begin of Workbench. So there is no problem if I ...
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Defining a Query with Multiple Values

I have been trying by best to create a definition query which would select a group of municipalities from among the many in my state. I have tried commands of all sorts of variations from "Name"='...
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1answer
853 views

PostGIS Intersection and Summarise Attributes

I am usually an ArcGIS desktop user, but keen to start using PostGIS more and I have a really big bit of processing to do. Not sure what functions to use, hopefully someone can help. I have a polygon ...
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PostGIS and invalid SRIDs

I'm having difficulty with a PostGIS query. I am trying to query my database (world_countries) using a bounding box drawn on a google web map. The objective of this query is to find any countries that ...
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125 views

How to rectify the walls of buildings in PostGIS?

I need an operations in PostGIS to eliminate intermediate vertexes in a polygon to rectify the walls of a building. I was revising http://trac.osgeo.org/postgis/wiki/UsersWikiExamplesSpikeRemover but ...
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714 views

Merge reversed linestring in correct order in postGIS

I want to merge linestring in the correct order in postGIS, but sometime they are reversed so something like this : select astext(linemerge(ST_union( ST_GeomFromText('LINESTRING(3 3, 2 2)'), ...
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Identifying topological relationships using PostGIS

I'm trying to perform a basic typology analysis using PostGIS. My objective is to find any polygons that touch other polygons. To do this, I thought the ST_GetFaceEdges would work (reference). I want ...
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Mysterious MapInfo query syntax errors

I'm struggling to get what seems like a perfectly normal query to execute in MapInfo v10. In SQLite Manager (an excellent firefox plugin), this works as expected: SELECT area_name, street_name, ...