In a database, a mechanism for optimizing access to data based on the spatial column(s) of a data table.

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Building efficient multi geometry type database with PostGIS?

I'm trying to build a PostGIS database which must be able to store (multi)points, (multi)linestrings and (multi)polygons. The goal is to efficiently querying the data with ST_Intersects and other ...
2
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0answers
83 views

display issue in qgis 2.14 : features appear and disappear

I have several virtual layers in my project. One of them contains 6 lines. Depending of the scale, at least one line disappears from the canvas for an unknown reason. I heard that sometimes, creating ...
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1answer
262 views

How to disable spatial index creation by ArcSDE for Oracle Spatial

Working with arcsde 10.1 and oracle spatial 11g. I set the feature class in load_only_io before loading shape files. I am using geoprocessing tool (append) in arcgis to load shape file to ...
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0answers
32 views

What is the impact of changing grid sizes while applying spatial index on specified table in SQL Server 2014

I have a Feature class with millions of points of interest (contains OID and geometry columns) which is stored in ArcSDE along with other non-spatial datatables which are stored in SQL Server DB . I ...
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1answer
32 views

Using Postgis spatial index in st_distance operation based upon explicit SRID column

I have two large tables with data that spans over multiple regions of the U.S and needs a defined SRID column in atleast one the tables to denote which coordinate system should be used for ...
2
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1answer
66 views

Running Gevel on PostGIS 2.0

I have found Gevel, a tool enabling the visualization of the content of the GiST indices in Postgres. In particular, I am interested to use it to visualize the RTree spatial index in PostGIS. Does it ...
2
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2answers
72 views

Postgis Functional Index on st_pointonsurface() Ignored

If I define the following table... CREATE TABLE tbl_vast_importance( id bigserial PRIMARY KEY, geom geometry(MultiPolygon,4326) ); CREATE INDEX ON tbl_vast_importance USING GIST (geom); CREATE ...
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1answer
63 views

Bulk loading into pyrtree index

I'm using pyrtree to create an index for a point in polygon operation. I am currently trying to insert 1.8 million rows into the index and it takes more than an hour to do so. I am unable to use rtree ...
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451 views

Creating Shapefile spatial index programmatically in .NET?

I am creating a shapefile programmatically using DotSpatial using the following example syntax / pseudo code FeatureSet features = new FeatureSet(DotSpatial.Topology.FeatureType.Polygon); ...
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67 views

Accessing the internal data structure storing Postgis spatial index (PostGres GiST)

I am curious about how the internal data structures and storage mechanism of the spatial GiST index in Postgis. In Oracle, I used to like to show how the SDO indexes were "just another table", and how ...
2
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0answers
15 views

PyQgis - How to update a spatial index?

I am trying to speed up a QGIS plugin I wrote by adding a spatial index to a vector layer. The aim of my plugin is to simplify a line network by merging some of its features, based on some criteria. ...
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44 views

QgsSpatialIndex partial or complete overlap

I'm working on adding some functonality to a QGIS plugin. It currently uses a QgsSpatialIndex to efficiently compute whether the features of a vector layer intersect (potentially millions) of ...
2
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1answer
246 views

Basic sp-gist indexing?

Please forgive a very, very elementary question. I am using a PostgreSQL 9.3.5 database, and one of the tables stores longitude and latitude. (These are two separate columns.) I would like to do ...
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0answers
36 views

“Spatial index is to small” from same geodatabase

I have an interesting thing going on. I have an ESRI geodatabase which contains numerous (versioned) featuredatasets. When I export for example a featureclass to a shapefile and try to import the ...
2
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0answers
38 views

In memory spatial index for frequent updating point objects

Is there any in memory spatial index specialized for frequent updating point objects? The dataset will be moving cars, most likely update per second but with millions of them. The project will be ...
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2answers
2k 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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1answer
33 views

Indexing PostGIS table by tile boundaries

I have a PostGIS table with 2M rows, all Points. I'm creating tiles from the data, but it's quite slow. Although I have the normal geometry indexes enabled on the table, I wonder if it's possible to ...
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3answers
2k views

Optimize nearest neighbor query on 70 million point cloud on SQL Server 2008

I have about 75 million records in a SQL Server 2008 R2 Express database. Each is a lat long corresponding to some value. The table has geography column. I am trying to find one nearest neighbor for a ...
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1answer
1k 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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18 views

Spatialite Index not matching

I have a dataset containing GPS points I store in a table with a geometry column. I use the following code to populate my table. CREATE TABLE STOPS_GEO ( stop_id TEXT PRIMARY KEY, stop_desc TEXT, ...
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1answer
48 views

nearest N objects (points) [closed]

i'm searching nearest ten neighbor points from a given point. When i use this query: SELECT id, geom, ST_Distance(geography(geom), ST_GeographyFromText('SRID=4326;POINT(-0.22707 51.5444204)')) as ...
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1answer
472 views

Are there trade offs between using a geohash vs using a quadkey as a spatial index?

QuadKey Bing Maps uses a quadkey structure for their tiling scheme. Here is an overview of the concept http://msdn.microsoft.com/en-us/library/bb259689.aspx. GeoHash A geohash seems to be the more ...
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111 views

how to use spatial index in spatialite query

I posted this question originally nearest neighbor query in SpatiaLite. Thanks to the answer given I was able to get the query working on some test data. However I am having trouble applying a spatial ...
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3answers
4k views

Poor Performance when using Spatial Indexes in MySQL

Re-post of a question asked on Stack Overflow when it was suggested this would be a better forum. I'm trying a little experiment at pushing a data set which is not geo-spatial but fits it quite well ...
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0answers
179 views

Using a ShapeFile spatial index with ogr2ogr and ogr.DataSource.ExecuteSQL()

I created a spatial index foo.qix for a foo.shp with ogrinfo -sql "CREATE SPATIAL INDEX ON foo" foo.shp However, when I do a query with ogr2ogr and look at it in strace, it doesn't use that index: ...
2
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1answer
76 views

OpenStreetMap Data Lookup Slow in PostGIS

I have imported OpenStreetMap data (Europe) into PostgreSQL 9.1 database with the help of osm2pgsql and filtered out everything expect administrative areas. I have GIST index for polygon (way) column. ...
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1answer
60 views

Problem with spatial index PostGis

I'm using Postgis 2.1. I have this table with about 50k rows: CREATE TABLE rilevazioni ( geom geometry(Polygon), stimolo integer, tmstmp timestamp without time zone, id bigserial NOT NULL, ...
2
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2answers
392 views

3D KNN index in PostGIS

I am looking for a way to do fast KNN queries on a dataset of 10+ million 3D points (and growing). I was hoping PostGIS would do the trick with its new <-> and <#> operators, but they don't seem ...
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1answer
78 views

ArcSDE PostgreSQL configuration parameters for Spatial Index?

I wonder why there is not any configuration parameter (DEFAULT Keyword) for spatial indexes in Arcsde for postgres. In ArcSDE for Oracle we have S_STORAGE,S_INDEX_SP_FID,S_INDEX_ALL parameter for ...
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3answers
2k views

Spatial index to speed up the query

I have spatial table in PostgreSQL 9.2 / postgis 2.0 that I have to extract some information from it. But my query is hopelessly slow. How could I make use of spatial index to improve the performance ...
2
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4answers
614 views

PostGIS doesn't use spatial index with ST_Intersects

I imported the data from openstreetmap using osm2pgsql and copied it another table structure. If I made a query for containing rows using st_intersects, st_contain or someone else, postgis don't use ...
5
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2answers
883 views

Understanding the Use of Spatial Indexes

I'm having trouble understanding the use of spatial indexes with RTree. Example: I have 300 buffered points, and I need to know each buffer's intersection area with a polygon shapefile. The polygon ...
3
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2answers
754 views

create polygon adjacency matrix using python

I am trying to create an adjacency matrix from a set of polygons. That is, I have a bunch of polygons and I want to identify which polygons have a common edge or "touch" each other. Once I find this ...
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2answers
844 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 ...
4
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3answers
1k views

How to efficiently access the features returned by QgsSpatialIndex?

The PyQGIS Cookbook explains how to set up the spatial index but it only explains half of its usage: create spatial index — the following code creates an empty index index = QgsSpatialIndex() ...
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42 views

Cannot see shapes in ArcCatalog or ArcMap after creating spatial indexes? [closed]

I created a spatial index on a feature class, but when I try to load it in ArcMap, I cannot see the shapes. When I remove the spatial index, I can see the shapes in ArcMap/ArcCatalog.
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1answer
549 views

PostGIS doesn't use index for spatial query

I can't get PostGIS 2.1 running on PostgreSQL 9.3.5 to use a spatial index even for the simplest queries. The whole dataset is 8 million points (population count grid from here ...
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0answers
81 views

Silly problem with spatial index?

I explain : I've got a points layer in .shp, it's allright, no problem with display( pan, zoom it's ok)… But when I create a spatial index, display of the map becomes crazy. It's not easy to explain ...
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1answer
56 views

Index to speed up ST_HausdorffDistance?

When comparing similarity of linestrings with ST_HausdorffDistance (or another type of similarity function), is there a way to use an index to speed up the search for similar linestrings?
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1answer
45 views

How to create my own remote sensing index?

Using Landsat images how do I create my own indices to extract particular landuse? Are there any tool/ software for creating indices?
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58 views

Match housenumbers on buildings (special case of point-in-polygon-test)

Task with example I'm working with geodata (country-size) from openstreetmap. Buildings are often polygons without housenumbers and a single point with the housenumber is placed within the polygon of ...
0
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1answer
239 views

Spatial search performance on a collection of Points in a PostGis database

Let's assume you have a huge PostGis spatial table (using Postgresql 9.2, postgis 1.5) : BIGTABLE ( p Point, someData varchar ) which contains millions of records. Each record has been created ...
5
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1answer
204 views

What are the PostGIS Raster Constraints used for?

My question is quite basic, but I have not found a simple explanation of why raster constraints are useful. I have worked with rasters in PostGIS for a while but only recently I realized that I do ...
5
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1answer
3k views

Fastest strategy for proximity searches in SQL Server 2012

This is my very first question here, so bear with me! I'm implementing a back end for a mobile app which will have to do proximity searches to find nearby POIs (points os interest). I know it's a ...
1
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1answer
246 views

Geoserver WFS features query inaccurate using SQL Server Backend with spatial index

I´m using Geoserver to query features through WFS in an Web Application with Openlayers as client. The queried layer is using SQL Server as backend storage. When applying a spatial index to the ...
2
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2answers
537 views

How to work with the STRtree Index when object in the index change it's position?

I'm work with the NTS(NetTopologySuite), I get large amounts of Point geometries, for fast querying the point object, I make the STRtree Index like this, STRtree tree = new STRtree(); foreach (var p ...
3
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1answer
223 views

How to quickly extend PostGIS's R-Tree implementation?

I am working on a problem where along with data points location, I also have information about the connectivity between points.(Think a graph of points, where an edge denotes some relationship) My ...
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3answers
3k views

How to properly utilize DWITHIN Spatial Filter in OpenLayers

Given the following code: var points = []; points.push(new OpenLayers.Geometry.Point(-110, 38)); points.push(new OpenLayers.Geometry.Point(-108, 40)); var lineString = ...
4
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1answer
187 views

Does QGIS automatically use spatialite spatial indexes?

When you write a query in spatialite you have to manually join your query to the spatial index for that index to be used to speed up the query. When QGIS displays data does it take advantage of any ...
0
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1answer
95 views

Is there a way to force ArcCatalog to use a specific tessellation scheme for a SQL Server spatial index?

If I Recalculate a spatial index from ArcCatalog, the tessellation scheme is always set to "Geometry Grid". Even when the previous index was Geometry auto grid. ArcCatalog always changes it back. ...