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

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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 ...
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290 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 ...
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470 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 ...
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2answers
798 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
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399 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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368 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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1answer
110 views

Is it possible that a good spatial index just cannot be made?

I have about 6 million rows with geography spatial features - they are all 1000 meter radius hexagons all over the US. There are a couple hundred thousand that would have been NULL, which I updated ...
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1answer
336 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 ...
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3k 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 ...
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830 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 ...
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2answers
543 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 ...
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620 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 ...
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How to convert MultiLinestring to Linestring?

I have a multiline string and want to convert it to a linestring in order to use some functions that only work with linestrings. I used ST_Dump() and got a collection of my geometries. If I merge them ...
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4answers
1k 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 ...
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2answers
2k views

Bounding box for PostGIS table

Is there an easy way to get the bounding box for an entire table in PostGIS? Thanks
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3answers
352 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 ...
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236 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 ...
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278 views

SQL Server data modelling + spatial data = what book?

What recommended book can you provide about data modelling for geographical spatial data (geometry) in SQL server?
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682 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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791 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 ...
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213 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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295 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 ...
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1answer
987 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 ...
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99 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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1answer
433 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", ...
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2answers
603 views

Using a bounding polygon, instead of a bounding box

I've got a large set of LAT/LON coordinates. Up until now, when I needed to select out those that fell within a certain region, I'd just create a bounding box using some MINx, MAXx, MINy, MAXy values ...
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1answer
236 views

How to populate SQL options for parameter in ArcGIS 10 tool?

I'm trying to create a tool where individuals can select a variety of records using a SQL expression that is then passed to a calculation. I can add a parameter under the tool, and select SQL ...
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490 views

Calculate Field based on field value in a second table

I have a table in a MSSQL Server Enterprise SDE database. I need to join a table from a MS SQLExpress Workgroup SDE database and then calculate 11 fields in the Enterprise table based on values in ...
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3answers
459 views

How to select a number of rows based on current sort order

I would like to be able to select a certain number of rows from my attribute table based on their ordering and not their attributes. For example, if I sort by ObjectID, I then want to select the top ...
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1answer
1k 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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212 views

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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2answers
462 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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924 views

How to automatically create 2D-point features from addresses in an SQL database

I currently have an SQL-Table which contains our buildings. I already added the table and now want to create features ( 2D-Points ) from that information. The biggest problem I have is that the ...
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263 views

how to cast integer to float in an ogrinfo sql statement?

I have a shapefile for which I would like to add the values in a column. As the sum exceed the capacity of an integer, I need to cast values to a float. I tried the following: ogrinfo -sql "SELECT ...
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3answers
544 views

Incorporating SQL Statements in Model Builder

I have a point data set where each point has a unique operator associated with it. I'd like to select by attribute = operator name and generate a new shapefile for each operator containing only the ...
4
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1answer
597 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. ...
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1answer
390 views

Geodjango insert statement: psycopg2.IntegrityError: violates check constraint

Why is the following INSERT statement throwing this error? INSERT INTO domes_place (placeid, structidx, oscode) VALUES ('10', '1', 'POINT(51.121282945772 1.3138398501222)'); psycopg2.IntegrityError: ...
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2answers
220 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 ...
4
votes
1answer
132 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 ...
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1k views

How to join two tables using date, time, lat and lon as common field?

I am sorry if the question is elementary but I did not find any clear discussion or guide to understand how to run a query in postgresql. So that a pointer to another website would be also useful. ...
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2answers
1k views

Publish SQL Views from Postgres/Postgis to Geoserver

I've trying and reading how to publish a Postgres/Postgis View in Geoserver. I know that I can create an SQL View in Geoserver, but I'd like to define the View in Postgres, not in Geoserver. Does ...
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3answers
305 views

arcgis10 filter dataset

Using ArcGIS 10 SP-4 I have a large dataset of sites that needs to be filtered down to a usable size. There is an attribute for the site_ID and another one for the site_type. There are duplicate ...
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1answer
235 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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1answer
470 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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1answer
209 views

PostGIS Query: All rows within 1 hour of each other which intersect

I'm using postgres (postgis) and i want to perform a query that returns all rows which geometries intersect and have a timestamp within 1 hour from each other. What would the SQL statement look like? ...
4
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1answer
276 views

Sort by geometry using INHERITS?

hope everyone's doing well. I have a statewide point data set (parent table: 600K rows, 500 columns) I need to analyze at multiple scales based on several different spatial divisions. I'll also need ...
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1answer
544 views

Error using ST_AddPoint for adding a new point to a polyline in PostGIS

I have two PostGIS tables, one where I store points, named "nodes" and another with where I store multilinestrings, named "lines". I'm trying to append a new vertex to a line using one of the nodes ...
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1answer
1k 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 ...
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1answer
1k 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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3answers
138 views

Sql syntax in Model builder

In ModelBuilder I am trying to perform the following query, using the select by attribute tool. I am having great difficulty with the sql syntax. What I am trying to do is Select Top 3 (Avg) Price, ...