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

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6
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3answers
101 views

Select all polygons that are completely within a circular buffer

I made several buffers around some points. Now I want to select all polygons that are completely within this buffer. My problem is that I also get the polygons that are partially outside of the buffer....
6
votes
2answers
1k views

Using integer variable in where clause of ArcPy script?

I'm trying to include an integer variable in the SQL where-clause of a tool like this (ArcGIS 10 Python script): newR = ExtractByAttributes(inR, '"IntField">=2508') where inR is an integer ...
6
votes
2answers
233 views

How can I cluster all points in a postgis table together based on their distance from each other?

I have a PostGIS (in postgres 9.3) table which has Points. I want to figure out the "clusters" in the data. If 2 points are < X distance apart, they should be added to a cluster, and this should be ...
6
votes
1answer
1k views

Spatial joins in OGR SQL

I have seen that OGR supports it's own form of SQL, I was wondering if it's possible to do spatial joins. Something like select all objects where one intersects the other. I did have a look around ...
6
votes
1answer
1k views

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 ...
6
votes
2answers
2k 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 ...
6
votes
1answer
535 views

Clarification of Logical Operators in a PostGIS Database

The following query returns this result: select count(*) from a , b where a.geom && b.geom; count ------- 66514 On a postgis 2 database. What does the logical operator AND (...
6
votes
1answer
329 views

Postgres/postgis cursors

I have a road network with StreetName and min/max address ranges for each segment (ie- StreetName = 'Main St', Min = 100, Max = 199). I also have individual address points with similar information (...
6
votes
2answers
2k views

Does SQL Server need extensions to do spatial?

Does SQL Server need extensions to do spatial like Oracle does? Just wondering if there will be extra costs for implementing a SQL Server backend to SDE. Thanks
6
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3answers
856 views

How to Comment Out Definition Queries

I use Definition Queries a lot in my daily GIS life, but one of the many things I've found annoying about ArcMap is the inability to comment out Definition Queries. I'd like to have this option as ...
6
votes
3answers
384 views

Are there any open source Python modules compatible with arcpy that will allow complex SQL queries?

I am trying to handle string (non-geometry) duplicates in a large attribute table of a shapefile without having to convert to gdb and back or connect to a postgres db. I need to be able to use a count ...
6
votes
1answer
724 views

SQL “Case” statement when count(*) is 0

I am trying to write the following SQL command using case clause. with x as (select the_geom as geom from table1 where st_dwithin(the_geom, st_setsrid(st_makepoint(28.959495,41.019913), 4326), 0....
6
votes
4answers
2k views

Sqlite, Python 2.7 and Spatialite

I am trying to spatially enable my sqlite database: import sqlite3 db = r'c:\temp\mydata.sqlite' conn = sqlite3.connect(db) conn.enable_load_extension(True) cur = conn.cursor() cur.execute(r"SELECT ...
6
votes
2answers
8k views

ARCGIS 10 definition query to select the max value from a group

In ARCGIS 10 I am trying to do a Definition Query that will select the records that are the max values from a specific group. Here is what I have tried in the Query Builder but I am getting an "the ...
6
votes
1answer
2k views

Registering SQL Spatial View in ArcSDE and updating Row_ID?

I am having issues registering an inner join SQL view with a spatial column in ArcSDE. Any help would be much appreciated. Here is the background info: ArcSDE 10, SQL Server Enterprise 2008 R2, SQL '...
6
votes
2answers
2k 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 ...
6
votes
2answers
1k views

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 ...
6
votes
0answers
1k views

Getting ST_Difference between two different tables in postgis [closed]

One table has a series of grid squares in it, and the other has millions of voronoi polygons in it. I need to create a table that has the difference between the two of the them so that I effectively ...
5
votes
3answers
3k 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 "...
5
votes
4answers
4k views

Updating 30 Shapefiles, adding attribute and populating based on data

I need to add an attribute to each shapefile attribute table in ArcMap, I was thinking to do it in SQL, but I'm not sure how to go about doing it since I'm very new to ArcMap. Can someone explain to ...
5
votes
3answers
21k 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 ...
5
votes
5answers
4k views

ExecutING SQL script in ArcGIS field calculator?

I am trying to transfer over row data from a table to columns in a shapefile table. There is a common "SA" variable between the two (i.e. the study area number) but there is more than one land use ...
5
votes
2answers
11k views

'Select by attribute' using python in ArcMap 10

I need to select a feature using SQL before zooming to it in python. What I'm looking for are replacements for the commented lines in this code: import arcpy parcel_num = "123456" mxd = arcpy....
5
votes
2answers
9k 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 | ...
5
votes
2answers
87 views

SQL MAX Subquery in arcpy.MakeFeatureLayer_management

I am having an issue with subsequent subqueries in making a feature layer in arcpy. My table has fields: OBJECTID, pointid (long), grid_code (double) I can successfully extract MAX(grid_code), ...
5
votes
2answers
820 views

How can I extract all distinct values from a PostGIS Raster?

I am working with an integer raster in PostGIS 2.1 and I would like to extract all distinct values in that raster. I was hoping to be able to do something along the lines of the following query, but I ...
5
votes
2answers
1k views

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 ...
5
votes
2answers
150 views

QGIS expression builder include relation attributes

I have a set of symbols based on a table in postgis such as this id|type|action_1|action_2|geom In QGIS I have this table symbolised using a rule expression which works effectively. However this ...
5
votes
2answers
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 ...
5
votes
3answers
96 views

Limit to number of items using 'IN' SQL syntax in arcmap/arcpy?

I'm writing a python script that uses 'NOT IN ('a', 'b', ...)' statements on very large lists (like comparing 500 items in one feature class against >10k items in another) and am getting weird ...
5
votes
2answers
1k views

Selecting maximum Value based on other field using ArcMap?

I have problems with a SQL query. The table looks like this, it is a point feature class both in postgres and file geodatabase, I am working in ArcMap. name: elev_p HEIGHT AREAid 100 1 200 1 ...
5
votes
1answer
6k views

Arcpy cursors, WHERE clauses, and date/time fields

I'm having trouble making a selection of rows that meet certain date criteria using my arcpy.UpdateCursor(). I need to update records in a field in a geodatabase table with an ascending value based on ...
5
votes
1answer
424 views

How to filter points based on proximity while inserting into PostGIS?

I have a large amount of locations that need to be inserted to a PostGIS database. However, I'd like to aggregate these points so that if there's already a location, say nearer than a kilometer, then ...
5
votes
1answer
834 views

Spatialite SpatialSQL Query

I've been flummoxed by this query. I have a table of points, and a table of lines, and I am trying to return the point id and line id whenever the point is contained within a buffer of the line (i.e. ...
5
votes
1answer
75 views

Creating ArcPy scripting tool with dropdown box for sql expression choice

I am creating an ArcPy scripting tool to allow users to select a feature from a feature layer and then zoom to that selection. I have successfully created this tool and now am working on creating the ...
5
votes
2answers
1k views

How to run custom queries on vector layers and display results?

Is there a way to display the result of a query in QGIS? For instance : To get the total number of inhabitants : SELECT SUM( inhabitants ) FROM countries To get the total density : SELECT SUM(...
5
votes
2answers
2k views

How to export a PostGIS raster to PNG?

I have a raster which is split into 30 tiles and I want to dump them all into PNGs. I've read the documentation http://postgis.net/docs/RT_ST_AsPNG.html but still don't know how to dump it well. If ...
5
votes
2answers
408 views

Selecting POIs around specific buildings using PostGIS

The problem: I need to select, for each residential building in my table that has say at least 2 pharmacies and 2 education centers within a radius of 1km, all POIs (pharmacies, comercial centres, ...
5
votes
2answers
1k views

Optimizing Geometry.STIntersect Query

I am attempting to move simple Geoprocessing routines from ESRI based processes to SQL Server. My assumption is that it will be far more efficient. For my initial test I am working on an intersection ...
5
votes
1answer
70 views

How to use MAX SQL statement in ArcGIS?

I would like to use a MAX SQL query for a column in a definition query, where there records that are being queried are the MAXIUM from the field UPDATE_DATE_DATE while grouping by the field NUMBERCYLA....
5
votes
1answer
1k views

How to use %value% (from For iterator) in SQL expression of Calculate Field in ModelBuilder?

I have a shapefile with data of fish specimens and the coordinates where they were tagged for research purposes. One of the fields in the attribute table of these shapefiles is the fish length in ...
5
votes
2answers
2k views

How to find the nearest land mark from a given longitude and latitude?

I have a table called osm_places with place_name geometry, place_type and many other info related to the city. My database system is PostGIS. My requirement is: Given a latitude and longitude (...
5
votes
2answers
184 views

How to draw radius of a circular point buffer using PostGIS

I have generated circular buffers of points in a shapefile. The generated circles and points share a common ID/key, say pt_id. My question is Is it possible to use PostGIS to generate a third layer ...
5
votes
2answers
119 views

How to select random adjacent census tract

I have set of census tracts spaced out across a city and I would like to randomly choose an adjacent census tract to explore nearby demographic data. I'm not sure if there is an easy process for ...
5
votes
0answers
331 views

Geoserver create SqlView Layer with Geoserver Manager

I would like to register a new sql view layer to geoserver through the rest api. I am using geoserver-manager. The registration is ok, the layer is working fine, except wms getFeatureInfo, which ...
4
votes
3answers
12k views

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"='...
4
votes
3answers
956 views

How to create Where Clause from user input via Python list?

I am trying to perform a query based on values in a Python list. The where clause will then be used in an Update Cursor, so that the rows NOT equal to the values in the list will be deleted. This is ...
4
votes
2answers
1k views

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 ...
4
votes
3answers
1k views

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 ...
4
votes
2answers
303 views

Which Geodatabase supports SQL and is easily portable?

I want to choose the geodatabase type, which could be: permits direct sql queries. easily portable, because the app would installed in one computer. I know that the personal geodatabase is a good ...