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

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14
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6answers
4k views

A SQL console in QGIS

I know QGIS comes with its field calculator, which is not bad. It also comes with ftools which permits several operations on geometry and attributes. But we often need more control and I haven't seen ...
4
votes
1answer
629 views

Select by attribute expression invalid in python

I'm not sure how my expression is failing. Any ideas? inPoints = "points.shp" i = 0 arcpy.MakeFeatureLayer_management(inPoints, "pts") arcpy.SelectLayerByAttribute_management("pts", "NEW_SELECTION", ...
0
votes
0answers
72 views

Select By Attribute sql problems [duplicate]

Having trouble with this python code. I keep getting a ERROR 000358: Invalid expression" code for the select layer by attribute management statement towards the end of the code. Moved the data to ...
2
votes
2answers
340 views

CartoDB- Passing selected features bounds to map center parameter (Zoom to selected features)

Looking to build a light-weight viewer for some data we have hosted on CartoDB. I'm looking to have a user input their address into an input, pass a query to CartoDB and have the map zoom/pan to the ...
6
votes
3answers
1k views

Join intersecting lines with PostGIS

This is something that I'm almost ashamed to ask but I can't seem to get it to work for the life of me. I have a road layer with segments, each segment has a Road ID and a segment type. I would like ...
3
votes
2answers
845 views

Check if an object is empty in mapbasic

I have mapbasic code that manipulates the obj-column in a point-table. Some rows doesn't have any geometry so the obj-column is empty. My question is how to check if there is no object? All the ...
0
votes
1answer
205 views

Linked point geometries to linestrings in Spatialite

I have been parsing Canada's radio system frequency open data. It's a single large table per province, containing point geometries for each station callsign. Where a point-to-point link is defined, ...
1
vote
1answer
49 views

Using Like on Join Field

Ok, so this has probably been asked by someone else out there somewhere but I can't find it via google or this stack, so... I've got two tables from an SDE database (SQLServer Express 2008 r2) that ...
0
votes
0answers
21 views

Multiple cursors in sql for SDO_DIFFERNCE

This is a follow up to a previous question I had regarding sdo_difference. Now in this case I am trying to use cursors so that I can do it for all records at once.In the below code I select a list ...
1
vote
2answers
121 views

sqlite version error with ogr2ogr

I am trying to randomly select some points from a shape file using ogr2ogr and an SQL query via sqlite but it seems to baulk at the sqlite version: ogr2ogr -sql "SELECT * FROM probe_2004to2012 WHERE ...
1
vote
1answer
190 views

Multiple input shapefiles for ogr2ogr sqlite spatial operations

I'm running up against an issue doing a spatial operation requiring multiple input shapefiles using ogr2ogr and sqlite. I have: ogr2ogr -f "ESRI Shapefile" output.shp input.shp -dialect sqlite -sql ...
0
votes
1answer
44 views

Wrong output wth group by and aggregate function in spatialite

I have a grid and for every cell I want to set the column "landuse" according to the largest intersecting polygon. SELECT grid.PKUID, landuse.landuse, ...
0
votes
0answers
132 views

Date Parameter in model builder - ArcMap

Basically I'm building a model where the user has to select the data from a drop down list and the result is executed. I have a problem when trying to pass a date as a parameter. Below you can find ...
0
votes
1answer
628 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
0answers
81 views

Trying to load ThinkGeo shapefiles into SQL

I am new to GIS, but have a work project that I need to integrate CoastLine geometry data in to a report. I downloaded some of ThinkGeo's OpenStreetMap shapefiles and have tried to load them using ...
15
votes
4answers
5k views

What is the best way to join lots of small polygons to form a larger polygon?

I have the following layer using SRID 27700 in postgis: It's every administrative region in the UK, and (as you can see from the colour grouping) each of them has a text field specifying the county ...
3
votes
1answer
71 views

New attribute creation using ogr and regex

I've got a folder full of dxf files with elevation values included as part of a long text attribute. I've written a regex expression to extract the elevation value, and would like to add it as a new ...
7
votes
2answers
3k views

PostGIS: Find points that lie within a set of coordinates

I have a PostGIS db, and I want to find the points that lie within some region (a bounding box). I have two sets of coordinates, from which I can get all four rectangle points that form the box (if ...
2
votes
1answer
542 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
1answer
46 views

Could SQL performance be increased by storing rotations of the data?

I'm working on a project where this kind of SQL Psuedocode would apply: SELECT * FROM objects WHERE (distance My inputs are latitude and longitude, and my database holds latitude and longitude. ...
4
votes
1answer
148 views

How to query nearest date in ArcGIS Server REST?

How to query nearest date (today) in ArcGIS Server REST? Table: ID NAME DATA 1 test 2013-06-01 13:00:00 2 test1 2013-06-01 16:00:00 3 test2 ...
3
votes
2answers
556 views

GDAL SQL syntax to add field an put values

I try to make a new field in my attribute table and put in values from another field after converting from character to integer but can't get the right syntax. I run this as shell-script in MSYS. cd ...
0
votes
1answer
319 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
0answers
159 views

Select a distinct attribute with maximum shape area

I am trying to manipulate a large dataset containing a lot of sliver polygons resulting from an overlay operations. (The eliminate tool is very time consuming to generalize them.) I identified the ...
6
votes
1answer
8k views

How to use Select by Attributes query with semicolons?

I am trying to select multiple (50 or more) unique numeric records using ArcGIS 10's "Select by Attributes" using semicolons ';' after each record which it verifies as good to go. Please see screen ...
4
votes
2answers
163 views

Maximum length of WHERE clause with IN statement

I need to get all features from feature class where their field value matches to input array. To achive this one may set IQueryFilter.WhereClause property similar to 'FIELD_NAME IN (array[0], ...
5
votes
1answer
192 views

ogr2ogr selecting features by attributes

I am writing a shapefile after some processing; however, in the final step I need to do some selection by attributes from the the shapefile. I am using the command in a shell with the aim of using it ...
0
votes
1answer
217 views

Vertex point is returning None

I have this multilinestring that has 48 NPoints. When I execute ST_PointN(line,5) it returns none. And to continue on, it returns None for everything after index:2 up to index:48. This is how my line ...
1
vote
1answer
143 views

Mapinfo SQL Query for compare for edited data in tables

I have a table that contain several columns, each has their own data. then, someone have made some change in the data (just a little one data editing). how do i know later what data have been ...
2
votes
1answer
86 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 ...
6
votes
4answers
3k views

ST_Intersection slow query

I am trying to perform an intersection between two layers: Polyline layer representing some roads (~5500 rows) Polygon layer representing irregularly shaped buffers around various points of interest ...
6
votes
3answers
2k views

How to find nearest neighbors between two tables with point locations in SpatiaLite?

I have started playing with SpatiaLite today and already stumbled upon a problem. For each point location stored in tableOne I would like to select one, nearest (linear distance) point from tableTwo. ...
6
votes
2answers
618 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 ...
1
vote
0answers
41 views

Selecting a bounded area within a raster

I am new to postgresql. I have imported a 256kb sample raster (.tiff) into postgres with tilesize 100x100. Now I need to select the area (rectangle) from the center of the image using sql query. Then ...
8
votes
1answer
844 views

How to trace SQL queries sent by ArcGIS Server (ArcSDE) to Oracle database?

I'd like to generate a log file containing all SQL queries sent by ArcGIS Server (ArcSDE) to Oracle database. Is there a way to do so? I'm using Oracle 11g and ArcGIS Server 10.0 on Windows. ArcSDE is ...
0
votes
1answer
639 views

SQL to get points within a certain distance

I am new to using spatial data types in sql server. I have managed to create a column of Approx 50,0000 geometry points (from x,y data) and would like to find out which (count number of) points are ...
2
votes
3answers
1k views

Inserting polygon centroids into an additional column in PostGIS

I'm trying to calculate the x and y centroids for a table using ST_Centroid. The documentation says that it returns the geometric center of a geometry. I first made a column X: ALTER TABLE ...
0
votes
1answer
66 views

Looping on the Select_analysis tool

Im trying to perform a loop on the Select_Analysis tool in Arcgis. Code looks like this: inputfile = open("locality.txt", 'r') # locality.txt is a txt file of locality names loc_list = [] for line in ...
3
votes
1answer
1k views

What expressions for QGIS field-calculator?

I do not understand what language I have to use in field-calculator and labels on QGIS: SQL or Python? And where I can find the possible script/expressions to use? in the image you can see the ...
0
votes
0answers
127 views

Geoservices REST JSON to SQL Server Geometry using Python

I'd like to hit a Geoservices REST endpoint (below) to return json and push this into a SQL Server Geometry table using Python. Ok so I can achieve this via ogr using below via command line: ...
0
votes
1answer
203 views

ArcGIS - Help Using Oracle Function in Definition Query - No ArcSDE

I have set up a Query Layer pointing at an Oracle table with a SDO.Geometry column, and that is working and behaving fine. However, when I am attempting to set up a definition query that calls a ...
1
vote
0answers
107 views

How can I retrieve/query data from shape file for forms/grid in website?

I've made a site using openlayers and geoserver. currently im serving WMS layers from geoserver (shape files). I want to add in my site a search form that the user can search for data (which I have in ...
2
votes
2answers
306 views

What is faster for geoprocessing (intersect) big shapefiles?

I have 200 Mb shapefiles of polylines downloaded from OSM. I've been working with QGIS 2.0 in Ubuntu 64 Bit 8 Gb RAM to make some geoprocessing tasks and it's taking 2 days for processing. Once I've ...
2
votes
1answer
257 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 ...
2
votes
1answer
475 views

How to use GROUP BY with arcpy.da.SearchCursor in file geodatabase?

fc = "C:\Users\AuxS3-4\Documents\ArcGIS/Default.gdb\Malla" fields = ('OBJECTID','Sentido','Carriles','idMalla') sqlclause=(None, "GROUP BY Sentido") cursor = arcpy.da.SearchCursor(fc, ...
2
votes
1answer
90 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 ...
3
votes
2answers
289 views

Change polygon “handedness” for SQL 2008

I have a few hundred shapes (polygons and multipolygons) each consisting of tens of thousands of points that I am trying to get into SQL 2008. Unfortunately, the shapes I have tried to import are ...
3
votes
4answers
7k views

Using String Functions (LEFT, RIGHT, MID) in Select By Attributes against a File Geodatabase using ArcMap 10

I finally (albeit reluctantly) made the switch from a personal geodatabase (pGDB) to a file geodatabse (fGDB) not too long ago. The main reason it took so long to switch has to do with how Select by ...
1
vote
2answers
578 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
249 views

Creating a model to run a complex query

I'm just a rookie when it comes to creating models in ArcGIS. I have two shapefiles from which I need to calculate an AVG and a MAX erosion rate for individual properties. The two shapefiles are: ...