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

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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 ...
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1answer
498 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
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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
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3answers
765 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
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1answer
506 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), ...
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350 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 ...
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4answers
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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 ...
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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 ...
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1answer
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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 ...
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2answers
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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 ...
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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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165 views

Spatial query too slow to handle bigger OSM extracts

I'm trying to compute some statistics for OSM data using PostgreSQL 9.3.5 and PostGIS 2.1.4. I started with a small bavaria extract which I downloaded from Geofabrik. The db schema is the normal API ...
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926 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
4answers
18k 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 ...
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5answers
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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 ...
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2answers
10k 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 = ...
5
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1answer
866 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 ...
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2answers
75 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 ...
5
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1answer
4k views

STIntersects - Update field to give me count of points in polygon

I have a points layer (dbo.ptLayer) Around 1M points Spatial Geometry Type (dbo.ptLayer.geom) No spatial index just yet, but will create one once data gathering complete. I have a polygon layer ...
5
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2answers
688 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
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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 ...
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2answers
137 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 ...
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2answers
259 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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2answers
937 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 ...
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1answer
5k 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
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1answer
409 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
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1answer
808 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
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1answer
317 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 ...
5
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1answer
2k views

SQL query to have a complete geojson feature from PostGIS

I would like to get a geojson feature with properties from PostGIS. I have found an example to have a feature collection but I can't make it works for just a feature. so far I tryed to modify the ...
5
votes
2answers
914 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 ...
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2answers
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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 ...
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406 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, ...
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2answers
513 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
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1answer
943 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
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2answers
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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 ...
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2answers
166 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
102 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
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0answers
312 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
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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 ...
4
votes
3answers
833 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
301 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 ...
4
votes
2answers
183 views

ArcGIS Model isn't accepting my SQL Query

I'm running a model that breaks a dataset into several dbf tables based on a query. However, only half of the query is being honored. The PopDenZone field is not being accepted and I am getting other ...
4
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3answers
677 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], ...
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2answers
62 views

In terms of SQL, what exactly is Query Layer's “Unique Identifier” doing?

When you make a link with a database using Query Layer in ArcMap, you must select a Unique Identifier, which ensures that the resulting Layer only has unique records in the Attribute table. In some ...
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2answers
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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 | ...
4
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2answers
1k 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 ...
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2answers
691 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 ...
4
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2answers
1k views

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 ...