A command used to retrieve information from a database

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How to group and count attribute data?

I have a problem with group same data to count it. for example, i want to group same code to one and count them. i can do it when i use MapInfo (Pic 1) but i can't in QGIS. (Pic 2: i can classify ...
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1answer
196 views

Mapinfo SQL Query for compare for edited data in tables

I have a table that contain several columns, each has their own data. then, someone have made some change in the data (just a little one data editing). how do i know later what data have been ...
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0answers
132 views

PostGis search query on hstore tags

I am writing a search client, to query postgis db. The search query will be, SELECT tags->'name' AS name,ST_Transform(way,4326) AS pt_lonlattext FROM planet_osm_point WHERE lower(tags->'name') ...
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3answers
151 views

How to search for several different features in the attribute table?

I guess my problem is a quite simple one, but the query builder and I have our difficulties, so maybe someone can help me. I have a long attribute table in QGIS and am trying to extract about 200 ...
3
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2answers
119 views

Determining closest representation of polygon as collection of points+radii

Have a bit of a tough question, which I realize there may not be an easy solution to. Figured what better place to ask. I'm attempting to transform a polygon into a series of arbitrary points with ...
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2answers
88 views

Reverse querying

Is it possible to run a reverse query? In other words, I have a master shapefile and a derived shapefile containing data extracted from the master file, but don't know what criteria the extraction ...
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1answer
76 views

Counting and sum by two layers

I´ve got to layers, both polygons. Layer 1 consists of propertiers, where ID is individually names. Layer 2 consists of lakes. The query I want is: Total count of squaremeters of lakes for each ...
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2answers
915 views

Merge lines with the same 'name' attribute on QGIS?

I have a shapefile with a few thousand lines, each is a street segment. I'd like to merge all features with the same 'streetName' attribute into a single attribute. I only really care about the name ...
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2answers
695 views

Why does ArcGIS Server not return data when querying joined fields?

I've been trying to help troubleshoot an issue that is very strange, and I think we've boiled it down to an issue with ArcGIS Server. We have a map service that shows up in the services directory as: ...
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1answer
27 views

Why do I suddenly get 'ERROR' as elements in my attribute table after doing a query in QGIS?

I was looking at an .osm file in QGIS using the OSM plugin; I was specifically looking at a country's lines layer. When I checked the attribute table just after opening the .osm, everything looked ...
2
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1answer
301 views

How can you tell if a RDBMS is an ArcSDE Geodatabase?

I want to know if there is any way I can query the RDBMS to determine whether it is an ArcSDE Geodatabase, or if I have to do it through ArcObjects. I am wondering if it would be enough to check if ...
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2answers
521 views

How to speed up spatialite-query using spatialindex?

I have got 2 tables, one of type LineLayer called strlayer, the other one is a PolygonLayer called blayer. The LineLayer contains two rows called fromBland and toBland that should be filled with an ...
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0answers
213 views

ArcObjects: How to Speedup Spatial Query to Feature Layer?

I have ROAD (POLYLINE) Shape File with more than 400,000 Records. I am working on a code which goes like this: Loop through all Feature of the Shape File Take First Feature Find the LAST VERTEX of ...
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2answers
241 views

oracle search against intersect of a region that covers the whole world doesnt find any records

I am new to Oracle Spatial, I am trying to implement a service that will take coordinates from a map, and search our database to find any geometries that intersect with that map view. I works fine for ...
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1answer
558 views

A couple GeoExplorer questions

I just started working with the OpenGeo Suite. I'd really like to use it for a County web map, but have a couple questions... 1) Is there a way to add a lat/lon or other X/Y location to the URL and ...
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2answers
474 views

Select by Attributes - If string has a letter

I'm running ArcMap 10.1. I'm using a File Geodatabase. I have a string coordinate field that I want to clean and some records have letters in it (mostly 'N' or 'E' or 'n' or 'e' e.g. '6213210N' or ...
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1answer
270 views

IQueryFilter where Clause quering two feature class at a time

I need to query two feature class at the same time using IQueryFIlter. For eg - FeatureClass -- A has field OBJECTID FeatureClass -- B has field OBJECTID what i am tring to do is -- IQueryFilter ...
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2answers
63 views

Find the majority area within another area

I have a survey grid overlaid unto several administrative areas. Both are polygon features and I have performed a union on both features in order to determine the areal contribution of the segments ...
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1answer
188 views

Circles created by points inside bounding box query - PostGIS

The table that i want to perform this query has 3 columns: id, the_geom and seen_count. The query i've been using to get points inside a bounding box is as follows: SELECT id, ST_AsGeoJSON(the_geom) ...
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2answers
632 views

ST_DWithin uses Geometry or Geography type

assuming I use the following query to match the locations to a poi within 10km distance: SELECT poi.poi_id, h.loc_id, (ST_Distance(poi.geom,h.geom)*111.111) as distanceinkm FROM iut_poi_transl AS ...
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3answers
123 views

Comparing polygon attributes that share the same parcel?

I'm new to ArcGIS, or at least anything beyond the basics, especially ArcToolBox. so the answer might be extremely simple. Basically I have one layer of building footprints, and another layer of ...
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1answer
94 views

How to select all cities in Germany from city and country layer?

I have 2 layers: layer_1: countries of europe, layer_2: cities of europe I want to create (and then save) a layer_3 which would be all the cities of Germany. Is there any good tutorial of how can i ...
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1answer
1k views

Why isn't my select by attributes query working?

I'm running ArcMap 10.1. I have a point feature class joined to a table and am trying to query a field. If I do [field] = 'TEST', it selects all the fields. But if I do [field] LIKE 'TES%', it ...
2
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1answer
450 views

Help building SQL query to get a list of streets of a city

From two layers in PostGIS (osm_places and osm_roads), I would need to have the roads belonging to a certain city. It would be fair enough to get the street names of all streets in a radius of X ...
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3answers
899 views

How can I export or query all hospitals from Open Street Map?

I'd like to extract all the hospital locations in the US from Open Street Map as a reference for my geocoding project. I know how to get all the OSM data for a small area with the QGIS plugin but not ...
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0answers
409 views

Select features within a country or bounding box effectively using PostGIS

I imported the planet OSM file into a PostgreSQL 9.2/PostGIS 1.5 server using osm2pgsql. I now want to select certain map features which lie within the bounding box formed by a countries borders, e.g. ...
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1answer
72 views

For each polygon, return yes/no value if it intersects another layer

I have a polygon grid overlaying several other polygon vectors. I wish to visit each polygon in the grid and ask yes/no if each of these layers fall within the grid cell or not. I can do this easily ...
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2answers
264 views

PostGIS, distance between two users

I have a simple table (location_test) with three column (name, geom , jid). geom is a geometry column with SRID 27700. I set the user's geometry position with: UPDATE location_test SET geom = ...
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2answers
1k views

Built a query for polygon Shapefile in R

I use the package maptools to read in Shapefiles in R. I would like to know if there is a function that can built up a query/subset to select only some Polygons based on a specific attribute in the ...
3
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2answers
125 views

How to query for a specific point, within a specific polygon?

I have a shapefile points layer, with each point representing either Marginal, suboptimal, or optimal conditions. I want to find only the marginal points within a specific polygon from my catchments ...
2
votes
1answer
352 views

Merge attribute data using spatial query in QGIS

I have 2 vector layers that I wish to correlate attributes - a shape file containing boundary polygons and a shape file containing point locations. I'm using the vector>spatial query tool to generate ...
3
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1answer
181 views

Filter contour lines in QGIS

I have a shapefile of contour lines, with an ALTITUDE attribute with the height ASL in metres. The source data is in 0.5m intervals, but I'd like to filter it down so I get contour lines at (for eg.) ...
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2answers
459 views

What are the options for working around the max number of records returned for a query task on ArcGIS Server 9.3.1?

I'm trying to return polygon features that intersect a larger polygon which defines my area of interest. It is working in some cases, but when the area of interest gets large (7000 intersecting ...
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1answer
923 views

Querytask/query - executed select

Is there a way to get to the query condition, which is executed under the querytask ? I have an example, which is actually a copy of this ArcGIS example ...
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1answer
225 views

How can I change SQL query through a layer of an action (python)? [closed]

I have three layers from three diferent database tables. When I click in other layer I want to change (with an action) the query of that three layers. How can I do that? Thank you
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3answers
590 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
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1answer
477 views

Reading OGC geometry data from SQL server using R

I would like to write a script in R that creates a map using OGC geometry data that is stored on a Microsoft SQL server. Is there a way to read OGC geometry data using a query passed from R? Maybe ...
0
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1answer
120 views

In QGIS can I show just the lines in a Postgis query? How can I do that?

I have three tables in Postgresql, each table with one layer of lines. I want to show the path of an initial line to another final. Is it possible executing a SQL query? Thanks My three tables are ...
4
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1answer
1k views

How to Find points in a Kilometre radius

I am new to PostGIS and GeoData. I need to find where the lightning has stroke by a period of time and kilometre radius based on a given location. I have given lon/lat and my table is: latitude ...
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1answer
394 views

How to get the nearest line to a feature?

I have features on map, and i want to get the nearest poly-line to each one. How to write spatial query to get the nearest one. I tried to use ISpatialFilter but i couldn't reach anything.
5
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1answer
1k views

How to speed up an st_intersects() query?

I have a "huge" spatial database: 72GB, 200 millions documents with geometries (points) I have a GIST index on the geometries the database: CREATE TABLE resources ( id bigint NOT NULL, accuracy ...
2
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2answers
430 views

Selecting lines occupying identical positions in MapInfo or QGIS

I have two shapefiles from a client, one is their entire network (complete with unique IDs) and another a selection I need. However the selection file does not have unique IDs but the entire one does. ...
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1answer
579 views

ArcGIS API Javascript - FeatureLayer from json: problem with queries and popup

Hello everybody I've tried this code proposed by Derek Swingley in JSFIDDLE: JSFIDDLE-FeatureLayer from JSON Everything "seems" to work fine, but not always. If you go down to the closer scale (level ...
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1answer
45 views

Isolate And Save Raster Features From Existing Multivalue Raster Map

I have Cyprus Corine map with 44 different types of land use. I want to run a raster calculator query or any other way to isolate the areas with codes 10 to 22 and 26 to 34, all other values 1 to 44 ...
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1answer
90 views

How to get routes in the database that intersects circle?

I have routes (linestrings) recorded in the database. I want to create a query which returns the routes that have some commonality with a circle whose center and radius are passed as parameter. I ...
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2answers
3k views

How can I more efficiently select related records?

Below is the code I'm using to replicate the "related tables" button in ArcMap. In ArcMap that button selects features in one feature class or table based on the selection of features in another ...
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0answers
175 views

Query to find lat/lon of a house by street.name & house.number

How can I get house coordinates (latitude, longitude) by street.name and house.number? If it is possible, how I can get it? Many thanks!
4
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3answers
2k 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. ...
9
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3answers
3k views

How to query all records (>1000) and export to csv?

I posted in arcgis forum but never got any answer. Can anyone tell me how to solve this? Assume you have a vehicle tracking records from Oct.1 to Dec. 31 with wind speed information. All data is ...
2
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1answer
161 views

How to best execute the same query on many different vector layers?

I have some vector layers in my project and I need to separate the polygones by area (I need a copy of all shapes > 2ha). I know how to do this for each separate layer (query) but is the a tool to do ...