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

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3
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1answer
303 views

Running PostGIS ST_ClusterWithin on large dataset?

I am trying to use the new ST_ClusterWithin in PostGIS 2.2 to help me aggregate building polygons that are within 5 metres. The source data has > 13million polygons. I ran the following query on a ...
3
votes
1answer
39 views

How to replace a directory using QGIS Field calculator?

I have a column called Hotlink full of incorrect directories and I need to edit them. They currently read C:/ABCD/filename.pdf and I want them to read C:/Maps/ABCD/ABCD/filename.pdf The script I'm ...
2
votes
0answers
46 views

Using Make Query Table to join featureclass with table using 2 fields

I would like to join a forest density table to a forest ownership featureclass in a geodatabase based on two columns in each (TPO_Owner and County_Nm) so I can populate the Density column in the ...
1
vote
1answer
29 views

Selecting the minimum point in a polygon

I am attempting to find the minimum point value within a polygon using ArcGIS 10.3. I have two datasets: 1) A series of polygons & 2) A series of points scattered about. After selecting a given ...
2
votes
1answer
883 views

Spatial joining syntax

A standard PostGIS point-in-polygon query might look like this. (example tutorial) SELECT p.*,b.polyname FROM points p, shapes s WHERE ST_Within(p.the_geom,s.the_geom) Imagine this was not a ...
3
votes
2answers
2k views

Deleting records from multiple, similar feature classes by attribute values using SQL statement in ArcGIS Desktop?

I have several hundred geodatabase feature classes which all have the exact same fields. I need to go through each of those feature classes and delete any records which match an SQL query (the same ...
2
votes
4answers
2k views

Finding center point of MULTILINESTRING using PostGIS?

How to find the center point of MULTILINESTRING, which lies on the multiline? I am using SQL in PostGIS
2
votes
0answers
49 views

How can I convert a shapefile from a single line segment to separate side segments using PostGIS?

I have a shapefile (STC) which is a single line segment per street with information for both the odd and even sides of the street. This .shp file has to be converted to separate side segments. To do ...
31
votes
11answers
18k views

How to connect to PostGIS database from ArcMap?

How can I connect to a PostGIS database from ArcMap? Solutions for ArcGIS 9.3, 10.0 and later are acceptable. Ideally, I would like to be able to perform spatially enabled queries and receive the ...
1
vote
0answers
24 views

Subset of spatial data causes slow SQL Spatial STIntersects

I've been having an issue were a specific subset of data causes an SQL spatial intersect to run extremely slowly. I am running sets of 1000 points against a subset of polygon layer to be intersected. ...
2
votes
1answer
69 views

Creating SpatiaLite View in QGIS?

Using these instructions (there are several other examples to find, all look the same and all of them seem to work) http://www.gaia-gis.it/gaia-sins/spatialite-cookbook/html/sp-view.html "Hand-writing ...
2
votes
3answers
2k views

Spatial join versus classical join

What are the main differences between a spatial join and a classical database join such as an equi (inner) join?
1
vote
1answer
190 views

SQL query works in PostgreSQL but not in GeoServer SQL View

I can't find a solution for this problem after a couple of hours of research. The query is: SELECT searchaddress('some string'); FETCH ALL IN mycursor; The function searchaddress returns a ...
1
vote
0answers
47 views

How to access a feature by specific field value using python ogr in an efficient way?

I have one point layer and one polygon layer with a common identifier attribute field called "N", same objects amounts but Feature IDs (FID) are different. I have to iterate on the first one and what ...
6
votes
2answers
232 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 ...
1
vote
1answer
31 views

PostGIS update statement returns wrong information

I have two tables in postgis with polygon data. Both are in wgs84. I want to update a column (column1) in the one table (table1) with information from a column (column2) in the other table (table2), ...
0
votes
0answers
137 views

Convert XY to Lat Long using SQL?

My organization is creating a 311 mobile app. The backend is all run through SQL and report emails are generated. We are grabbing the xy from the app and then want to translate it to Lat/Long to be ...
1
vote
0answers
36 views

How to transfer SQL variable back into ArcPy script?

I am trying to teach myself to access sql tables from an ArcPy script as part of a larger QC process. I am fairly certain that I have the sql statement correct (it works in SQL Server, albeit ...
2
votes
2answers
3k views

Formatting SQL queries for use in Arcpy?

I have to make an SQL query on a column having not adequat name "type_borne_id", I couldn't make SQL queries using arcpy.Select_analysis neither selectbyattribute, but when I use select_analysis ...
6
votes
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....
0
votes
0answers
29 views

How to Find Source and target using STBuffer And STIntersects in SQL Server?

I am using this query to find the source and target from Routes table, but it's not getting the correct result SELECT TOP 1 a.target FROM Routes a WHERE (ROUND((geometry::Point(73.0135494838,19....
2
votes
2answers
64 views

Is there a way to select all items within a circular buffer?

I want to select all the items within a circular buffer. Inside the buffer are multipolygons and multipoints. See the screenshot i have posted.
4
votes
3answers
1k views

Automatically creating 2D-point features for ArcGIS Desktop from addresses in 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 "...
0
votes
0answers
22 views

Is there a way you can see the spatial query that vector uses?

I am using geoprocessing-tools --> intersections to calculate which points are within my circular buffer. It works fine but I want to know what query(/code) vector is using so I can add some ...
4
votes
0answers
67 views

SQL SERVER 2012, Python subprocess, OGR

Need help with uploading shapefile with srid 102008 to SQL server 2012. I ran the ogr2ogr script in the ogr shell and it uploaded the shapefile within seconds but when I try using python subprocess to ...
2
votes
2answers
569 views

Finding Polygons which do not touch any other polygon in a single oracle database table

I currently have an oracle table of approximately 100,000 records - all of which are polygons. I want to find all the polygons which do not touch any other polygon within the same table. There are a ...
7
votes
3answers
444 views

Constructing Voronoi diagram in PostGIS

I'm trying to construct voronoi diagram from grid of points using modified code from here. This is SQL query after my modifications: DROP TABLE IF EXISTS example.voronoi; WITH -- Sample set of ...
2
votes
1answer
69 views

Use Postgis to convert wkb_geometry data type to geom datatype

How would I write an ALTER statement or otherwise to convert an existing imported data column from " wkb_geometry geometry(LineString,4326)" to a geom data type? I ask because I've moved to ...
3
votes
0answers
58 views

How to use pythons' GeoAlchemy2 to filter on dynamically generated Points?

I'm trying to do something like this SQL query in Geoalchemy2: SELECT district_polygons.district FROM markers, district_polygons WHERE ST_Contains(district_polygons.multi_poly, Point(markers....
2
votes
1answer
70 views

Using “SELECT DISTINCT” in SQL Query for Labels?

Working with ArcGIS 10.2. I'm using GIS data downloaded from SHA and I'm using it to label roads. I have three different features I've selected to label (different kinds of roads). To keep it brief: I'...
0
votes
1answer
99 views

Create a geoserver SQL view from Oracle SQL using a lat and lng column

I have a table in a Oracle SQL database in which I have a polygon geometry and two more columns of latitude and longitude. What I need is to show the points of lat and lng in a layer in geoserver. I ...
0
votes
1answer
37 views

ArcGIS Select largest N rows in group

I have feature class (Name: V1) in personal geodatabase with columns: Height [float] and Id [int] representing group number I need to do SQL query that will select eight highest 'Height' values in ...
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vote
0answers
18 views

deleting lines with smaller length and overlapping oracle spatial

I need to identifying polylines which are overlapping with each other and deleting them which is smaller in length in Oracle Spatial.
2
votes
1answer
846 views

Select top 5 most items in a geodatabase

I'd like to know what is the best way to select the 5 most expensive items (in terms of actual monetary value) in my geodatabase where i have a price field. Prices are not necessarily ordered but can ...
2
votes
1answer
287 views

Connecting QGIS, SpatiaLite and Python?

I am trying to connect with python code, QGIS and Spatialite, to do SQL query. I have read some tips and I tried with this code, but no add anything. Any Idea? uri=QgsDataSourceURI() uri....
0
votes
1answer
65 views

Arc 10.2.2 crashes when adding query layer?

I'm trying to add a query layer from an Oracle database into a blank 10.2.2. map. I enter the query, validate, finish, and the software thinks for a second and then just winks out. No error message,...
0
votes
0answers
22 views

if then else statement in Exponare?

I am currently trying to rewrite an SQL statement for Exponare so that if the user is not the administrator only certain attribute table columns are displayed should a query or selection be performed. ...
0
votes
0answers
23 views

Selection Based on Range of Values from another table

I'll try to explain this is as simply as possible. I've figured out how to create this table in SQL, no problem. But I'd like to have this done in python as part of a larger model. I have a feature ...
1
vote
1answer
55 views

Possible CartoDB SQL add-on?

Is there a possible add-on that will simplify the user experience when creating a SQL statement? More specifically, is there a GUI that would allow the user to create a SQL statement similar to ...
0
votes
1answer
89 views

Using function in SQL query with ArcPy?

I am trying to join points to polygons based on whether their addresses match as well as if the distance between them is less than 2500 feet. I defined a haversine function that computes the distance ...
11
votes
1answer
677 views

Nearest Neighbor Grouped Selection in QGIS

OK - so I have an interesting problem I am trying to solve. I have a list containing over 100,000 points in lat/long format which I have imported into qgis. Now, what I am trying to do here is group ...
3
votes
1answer
29 views

how to create a new row with a counted points in postgis

I have two tables in postgis (pgadmin). In one table there are points and in the other table there are polygons(provinces). The tables are both over the same location (Netherlands). I want to count ...
4
votes
0answers
104 views

Create polygon from lines in PostGIS

I'm trying to divide a polygon in smaller polygons from a line, but I think I can't use the st_split function. What I need is to create small polygons inside a big one, using linestring grid. I've ...
0
votes
0answers
41 views

Set alias for subfields when performing query

As mentioned within the ESRI-docs we can set an Alias for the subfields of an SQL-query performed onto a file-geodatabase as follows: IQueryDef2 filter = (IQueryDef2) featureWorkspace.CreateQueryDef()...
2
votes
1answer
54 views

How to create lines from coordinates?

I have a data table about national bus lines, with timestamps, vehicle IDs, line IDs (which line the bus is moving on), and coordinates(geom). I can add my points to QGIS on show them on OSM, but I'd ...
1
vote
1answer
47 views

Get lat and long in two columns as floats for all points in MULTILINESTRING in PostGIS?

ST_DumpPoints(geom) gives me something like this: ("{1,1}",0101000020E61000002DEDD45CEEB362C0CE1951DA1BC24E40) ("{1,2}",0101000020E6100000C94AD826F1B362C09D4B7BC72CC24E40)... Where I want it to ...
1
vote
1answer
24 views

postgis: union of faces of st_dump

I am trying to make a web application that renders 3D buildings (LoD1). I have a PostGIS (2.2.1dev) database which contains the 2D geometry of the buildings and the height. I used st_extrude to make a ...
1
vote
2answers
146 views

Checking if SQL where clause is valid with Make Feature Layer?

Unfortunately it's possible to apply an invalid SQL where clause when using arcpy.MakeFeatureLayer_management. This can cause issues later in a script. For example, I created a feature layer and ...
1
vote
3answers
68 views

Intersection of 2 Linestrings (not interpolated)

I am struggling with a query in POSTGIS I want to find linestring geometries where the geometries are containing the same point. I don't want to calculate the intersection points. I only want to ...
1
vote
3answers
49 views

Is a SQL String Aggregate possible in arcgis?

I have created a feature class from the results of a 1:many join between a table and a polygon layer in ArcGIS 10.3. The polygon layer contains land parcels and the table contains names. Where a 1:...