A command used to retrieve information from a database

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0answers
472 views

Cannot join feature layer with SQL Server table with query built in it in ArcMap

I need to join a feature layer with a SQL Server View with a common field in ArcMap. The View was successfully added to ArcMap as data table with some query built on it from Query Builder. When I ...
6
votes
1answer
735 views

Need to learn more about Precision and Accuracy

I am currently taking Introduction to Image Interpretation online and there is a section in it that talks about Precision and Accuracy. I wanted to know if someone out there has any good information ...
4
votes
1answer
6k views

How to filter features in a layer?

I am trying to display certain features in a shapefile-based layer using QGIS. I have found the subset function in the properties panel, which does exactly what i want, but is too tedious given that I ...
3
votes
0answers
318 views

How to get distinct values from multiple columns in GeoTools?

Is there a way to get distinct values from multiple columns in geotools? I know I can get unique values from a column like this: SimpleFeatureSource featureSource = ...
2
votes
1answer
989 views

Why does my PostGIS query fail with “current transaction is aborted”

I'm trying to create a vector layer in a QGIS project using a PostGIS query. QGIS is returning the following error: Query failed 1 cursor states lost. SQL: CLOSE qgisf1 Result: 7 (ERROR: ...
0
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3answers
644 views

How can I query and categorize a shapefile using MS Access?

Is there a way to categorize locations by lat-long in MS Access using caparisons to shapefiles?
6
votes
1answer
3k views

How do I perform a proximity search with Postgis?

OK, so I downloaded the Geonames database (cities1000) and wrote a small Ruby program to import them into my table (geo_cities). I then added geography column called geog. So after all of that, I ...
2
votes
1answer
1k views

PostGIS UPDATE Statement with ST_Contains(table1.geom, table2.geom)

I'm strugeling with a query I should write to UPDATE my dataset. First of all, I have 2 tables containing data and I need to mix it. Tabel 1 -- lets call it names: name_str the_geom (points) ...
2
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1answer
389 views

How to query OSM tags by polygon?

I do not know whether something like this is possible but nonetheless. If I understand OSM correctly all objects essentially have associated tags based on type of object (street, building etc) ... ...
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1answer
595 views

Administrative level and coordinates from Yahoo GeoPlanet WOEID

The Yahoo GeoPlanet data can be freely downloaded from: http://developer.yahoo.com/geo/geoplanet/data/. If I understand it correctly, each WOEID corresponds to a unique location on earth, with ...
5
votes
3answers
5k views

How to fix performance problem in PostGIS ST_Intersects?

I'm a newbie in postgis and I have a problem in query performance. This my query: SELECT DISTINCT ON (userid) userid ,ST_AsText(position), timestamp FROM table1 WHERE ST_Intersects ( ...
3
votes
1answer
5k views

Exporting query to identify what polygon certain points fall in using ArcGIS Desktop?

I'm using ArcGIS Desktop 10. I have shapefiles consisting of points (street addresses). I also have shapefiles consisting of polygons (ie, congressional districts, city council districts, etc... a ...
5
votes
1answer
3k views

How can i search over my layers with openlayers?

i have my map running over geoserver and openlayers. but i want to add a search box to find places in it. Well not specifically places but directions. The map reads the layers directly over geoserver ...
28
votes
3answers
2k views

Is there a “Select by Attributes” plugin/widget for ArcGIS Server JS API?

I'm hoping to find some existing code which emulates the "Select by Attributes" dialog in ArcMap, within the ArcGIS Server JavaScript API. Writing a hard-coded QueryTask is easy - I'm looking for ...
6
votes
1answer
744 views

How to sum area of polygons by values occuring in multiple fields?

My data has 2 fields holding landuse types, which both describe what is within the polygon. For example, the polygon may have Type1=Retail, Type2=Leisure Area= 1 but another polygon has Type1=Leisure, ...
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
2answers
462 views

ArcObjects ISQLSyntax with Oracle DB esriSQL_DelimitedIdentifierPrefix issue

New to stack exchange, heading over from the esri forums, it is great! I am trying to produce a query that I can use across all workspaces, naturally using ISQLSyntax. The problem I'm having is that ...
18
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2answers
5k views

How to select features with NULL attributes in QGIS?

I need to identify which features have null attributes in the attribute table of a shapefile. When i try [field]= 'NULL' it selects the features with value=0 (see picture) Suggestions?
3
votes
2answers
855 views

Why is my Definition Query not returning any records?

I am currently working on a mapping project and only need 8 tenements out of many to appear. I have gone into the query builder to complete this and unfortunately it will not work. Into the builder a ...
2
votes
1answer
4k views

Basic MapServer query of PostgreSQL/PostGIS database

I've just installed MapServer on a linux server and I am trying to understand how to display a basic map using a PostGIS database. I have displayed a shapefile in the browser, so I know that the ...
0
votes
1answer
277 views

Trouble with Request URLs sent by QueryPanel.js

I use the GeoExt QueryPanel, which I got working so far. I configured an osgeo proxy on my Apache Server, I use the override-ext-ajax.js and have the OpenLayers.ProxyHost = "/cgi-bin/proxy.cgi?url="; ...
1
vote
2answers
610 views

False DescribeFeature Request URL in GeoExt QueryPanel

I got the GeoExt QueryPanel working so far, it recognizes the layers available on my Geoserver but it is not able to get the attribute columns for the dataset. I configured an osgeo proxy on my Apache ...
0
votes
2answers
1k views

Mysterious MapInfo query syntax errors

I'm struggling to get what seems like a perfectly normal query to execute in MapInfo v10. In SQLite Manager (an excellent firefox plugin), this works as expected: SELECT area_name, street_name, ...
2
votes
0answers
755 views

Proxy trouble with GeoExt Query Panel?

I got the GeoExt QueryPanel working so far, it recognizes the layers available on my Geoserver but it is not able to get the attribute columns for the dataset. I configured an osgeo proxy on my Apache ...
5
votes
2answers
1k views

Practical way of managing polygons and unions of them

I have a table in PostGIS with a quite fine partition of a region, which I'd like to dissolve at two higher levels by means of two foreign keys (e.g. municipality and state). The partition is a real ...
0
votes
1answer
3k views

Query Feature using OpenLayers + MapServer

I'm trying to query a feature in OpenLayers, but it's returning just an image highlighted that is not possible to make zoom, pan and drag. My intention is to query a feature on the map like street ...
2
votes
1answer
1k views

troubles with osm2pgrouting

I'm trying desperately to write my first query in pgRouting using maps in osm format (as shown in http://www.carsonfarmer.com/?p=799). Im using Ubuntu 10.10 with Postgresql 8.4 ang postgis 1.5. After ...
9
votes
1answer
908 views

ST_ClosestPoint(line, point) does not intersect line

In my PostGIS database (PostGIS 1.5 on Postgres 8.4.1), I have two tables: roads (composed of linestrings) and crashes (composed of points). I've been trying to correlate each crash to a road, but I'm ...
1
vote
2answers
2k views

QGis import partial PostGIS layer using query builder

I'm sorry, but I'm terribly new to the GIS scene (and PostGIS & QGis). I have loaded a whole bunch of OpenStreetMap data into a PostGIS database and successfully drawn a map using Mapnik. Now I ...
3
votes
3answers
10k 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 ...
5
votes
2answers
457 views

Query a georss feed

I'm trying to consume a georss feed from a C# project. Can I have queries against a #georss feed? For example 'nearest item to Lon/Lat' or 'items contained in bounding box X' .? Thanks
1
vote
1answer
707 views

ArcGIS Server 10 - Query numeric field with string

In ArcGIS Server 10, I am running queries against several fields in a feature class. All of them are sent with the format FIELDNAME ='value' (all queries contain the single quotes). This is ...