A spatial data infrastructure (SDI) is a data infrastructure implementing a framework of geographic data, metadata, users and tools that are interactively connected in order to use spatial data in an efficient and flexible way.
2
votes
1answer
47 views
What is the syntax for querying a spatial column?
What is the right syntax to get all the points within the bounding box? The table consists of a lat and lng column and a spatial column "pt" generated from the lat/lng values.
calculated the topleft ...
2
votes
1answer
66 views
Visualiser for spatial query results
This question Whats the easiest way to get sql 08 spatial data onto a map? (and many other articles) recommends Craig Dunn's Geoquery, but all the download links appear to be kaput.
SQL Server ...
2
votes
1answer
288 views
What's the difference between POINT(X,Y) and GeomFromText(“POINT(X Y)”)?
I'd like to store some geometric positions in my MySQL database. For this I use the POINT datatype. Almost everywhere I read that the function GeomFromText should be used to insert data in the table.
...
1
vote
0answers
45 views
Combine Oracle locator instance with Oracle spatial instance with db link
we plan to have two oracle databases, one with oracle spatial installed, the other one just has the locator option.
Is it possible to create an oracle database link between the two databases in order ...
4
votes
1answer
126 views
T-SQL and GPS co-ordinates
I'm looking to store GPS co-ordinates in an MS SQL Server DB for location matching of users with GPS-enabled mobile phones.
I've read about STDistance on MSDN, but it only appears to exist in SQL ...
0
votes
2answers
209 views
migrate SQL Server geography data to PostGIS geometry data
I'm trying to use SSIS to transfer point data from a Geography column in SQL Server 2008 R2 to a geometry column in a Greenplum (Postgres 8.2.15) database with PostGIS. I know there's a way to do the ...
2
votes
1answer
259 views
MongoDB geospatial query with sort - performance issues
I have query (which is very slow ~2,5s):
db.markers.find({ latlng: { '$within': { '$box': [ [ -16, -140 ], [ 75, 140 ] ] } } }).sort({_id: -1}).limit(1000)
When I run explain for this query I get
...
1
vote
1answer
186 views
Convert spatial points data to line data for use in Line Layer in SQL Server Reporting Services (SSRS)
I have a query that returns the fields Order, Lat, Long, SpatialData, <OtherStuff>. SpatialData is a point.
I want to create a line layer that draws lines between my points based on the order ...
1
vote
1answer
282 views
$nearSphere returns too many data. What am I missing? Am I wrong? Is it a bug? Does other see the same thing?
I noticed that $near and $nearSphere returns completely different data and I got suspicious. After all, when latitude is near equator it sphere distance shouldn't differ a lot from euclidean distance.
...
2
votes
2answers
192 views
Error updating sql server geography type in trigger
I have the following trigger in my database:
CREATE TRIGGER dbo.triggerGeocodedAddressUpdate ON dbo.Party AFTER UPDATE AS
IF UPDATE(Latitude)
UPDATE pt
SET pt.GeocodedAddress = ...
0
votes
0answers
62 views
How can we combine $within and $nearSphere in mongodb
Say I am looking for the nearest location that contain the word seaworld.
I don't want mongodb to "scan" an area too wide.
So I want to limit it
I send
db.tablebusiness.find({ "LongitudeLatitude" ...
3
votes
2answers
231 views
Which graph database for search engine and gis?
I just learned there are "graph databases" out there, which are more suited for two applications "search engine" and especially "gis".
To avoid discussions weather a relational DB is better suited ...
1
vote
2answers
168 views
PostgreSQL : Is this because of locks(row level)?
I have a table with approximately 2.1 million tuples. Which has latitude and longitude columns. I am trying to convert this into a geographic type (point with SRID).
The function(procedure) I have ...
1
vote
1answer
158 views
postgis problem with shortest distance calculation
while working with POSTGIS pgrouting, for calculateing the distance between two roads(lines) i got the shortest_path function.
But the logic is based on Start_point(Start_id) and end_point(end_id) ...
0
votes
2answers
76 views
Trying to create PostGIS database
I am trying to create a spatially enabled PostGIS database. I am following the PostGIS documentation, http://postgis.refractions.net/documentation/manual-1.5/ch02.html#id2648455.
In the short ...
0
votes
0answers
22 views
A spatial query return no result when obviously there is result [duplicate]
Possible Duplicate:
Less restrictive query return less result due to simple removing one additional constraint
SELECT DISTINCT
TB.ID,
TB.Latitude,
TB.Longitude,
...
5
votes
2answers
196 views
Less restrictive query return less result due to simple removing one additional constraint
Look at this query
SELECT DISTINCT
TB.ID,
TB.Latitude,
TB.Longitude,
111151.29341326*SQRT(pow(-6.185-TB.Latitude,2)+pow(106.773-TB.Longitude,2)*0.98839228980165) AS Distance
FROM
...
4
votes
1answer
226 views
How does R-Tree outperform B-Tree for simple check if a point is within a rectangle
For things like find nearest neighbors, I can undertand that R=Tree can outperform B-Tree. R-Tree can kick out more obviously false points.
However, for simple check of a point in a rectangle, it's ...
0
votes
1answer
131 views
What database do most mobile start ups use? [closed]
mongodb?
MySQL?
PostgreSQL?
If someone would add pluses and minus, let me know.
Why I ask:
I am a mobile startup. I need a database that supports spatial indexes. The spatial index must be able to ...
1
vote
0answers
87 views
Why do we need myisam spatial extension anyway?
If just to determine whether a point is within a rectangle,
What is wrong with this query?
EXPLAIN SELECT DISTINCT
TB.ID,
TB.Latitude,
TB.Longitude
FROM
TableBusiness AS TB
WHERE
...
0
votes
0answers
140 views
Nearest neighbor search for 1.6 million points in myisam mysql
Say I want to find 20 closest business near me. Latter I want to see the next 20 closest, etc. Yes I have myisam. I have spatial indexes on the point. I am looking for actual command.
Note:
I am ...
1
vote
1answer
133 views
What is the SQL command to get 20 closest points from some center location
There are 1.6 million rows.
Must not compute distance for all rows.
Spatial index is available
This is the table structure. The name of the table is businessauxiliary. So yes I used MyIsam, added ...
1
vote
2answers
450 views
How do I get spatial index feature if I mainly use innodb?
My current strategy is to create another table in myisam that contains those spacial information. Then if I want to find 20 closest business, I'll just use join.
Is this a good idea?
7
votes
3answers
457 views
Can spatial index help a “range - order by - limit” query
Asking this question, specifically for Postgres, as it has good supoort for R-tree/spatial indexes.
We have the following table with a tree structure (Nested Set model) of words and their ...
2
votes
1answer
311 views
How to store GPS coordinate and search places in a radius from a NoSQL DBMS (like DynamoDB)
My team need a DBMS like DynamoDB to store large amount of data, principally places and coordinates.
I've considered to use some GIS-based DBMS (like PostGIS) with an index on the POINT, but DynamoDB ...
1
vote
0answers
106 views
PostGIS - Effects of polygons with large number of verticies [closed]
I have a large table that stores, among other attributes, a geometry type. I have a GIST index on this attribute. However, when I perform even the most basic queries [say, select count(*) from table ...
1
vote
1answer
696 views
Repair with keycache in mysql runs EVERY time. Can't even log why it's happening
I have a MyISAM table w/ ~1million rows and two indexes - one's a three-column key, and the other is a spatial index for bounded SELECT statements on a separate point column. My insert statements ...
3
votes
2answers
397 views
How do I design a database for continents, countries, regions, cities and POIs?
I am not a database designer so I'm having trouble designing database with GIS information. The goal is to create a system with continents, countries, regions (including states, sub-regions, ...
1
vote
0answers
33 views
sdo_tune.quality_degradation returning negative values
While running the sdo_tune.quality_degradation function on one of our Oracle databases most of the results were around 1 but a number had values like -556127.225.
Does this mean that these indexes ...
3
votes
1answer
118 views
Spatial data modelling tools
Is there anything like MySQL workbench for PostGIS? Something that supports SQL output and geometry types would be nice.
CLARIFICATION:
I am trying to implement the Land Administration Domain ...
1
vote
0answers
132 views
PostGIS: Remove stale/obsolete geometry columns from the geometry_columns table
I understand that the function Populate_Geometry_Columns() inserts records in the geometry_columns table for geometry columns that are not yet listed there. However, an invocation of ...
8
votes
2answers
3k views
PostgreSQL vs. MySQL - Advantages / Disadvantages with a spatial component
We are the in the process of building out a web application that has a spatial data component. In the beginning our spatial data comparisons will take a given point and return matched overlapping ...
2
votes
2answers
167 views
How do I set a geography point to be the North Pole?
I tried to execute this query on my SQL Server 2008 R2 instance:
UPDATE ITEMS
SET GEOG=geography::STPointFromText('POINT(0 90)', 4326);
SQL Server returned the following error:
...
2
votes
1answer
246 views
Creation of spatial index locks the table for hours
I used this code to create a spatial index in SQL Server 2008 R2:
BEGIN TRANSACTION
SET QUOTED_IDENTIFIER ON
SET ARITHABORT ON
SET NUMERIC_ROUNDABORT OFF
SET CONCAT_NULL_YIELDS_NULL ON
SET ANSI_NULLS ...
3
votes
1answer
127 views
SQL Server - Using spatial data
I'm using SQL Server 2008 R2 for real-time location aware service. The service mostly receives location data (lat/lon) from a user and returns locations around the user.
The data is being sent from ...
6
votes
1answer
195 views
Permission to create Spatial Index
Permissions required to create a Spatial Index on a table, for this BOL says:
Requires ALTER permission on the table or view. User must be a member
of the sysadmin fixed server role or the ...
6
votes
2answers
787 views
How do Application Like Yelp Retrieve distance information from data base efficiently
For example, say I have a table:
Business(BusinessID, Lattitude, Longitude)
All are indexed of course. Also there are 1 million records
Say I want to find businesses closest to 106,5, for example, ...
