One or more structured sets of persistent data, managed and stored as a unit and generally associated with software to update and query the data.

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52
votes
8answers
4k views

How do I get started with PostGis

I have been reading a lot about it, but I am struggling to find a good beginner's guide. Which tutorials/books do you recommend? My past experience involves python and arcgis. But I have never worked ...
35
votes
3answers
6k views

Are there newer routing algorithms (than Dijkstra, A*) in GIS databases?

There are works like Reach for A* from Microsoft researchers and Highway Hierarchies by Sanders and Schtolz (if I spell the name correctly) from Karlsruhe Uni. Both of them reduce the calculations ...
23
votes
9answers
4k views

Is there any way I can use a Key-Value store for geospatial data?

I have used many relational databases in the past, but I have also read about all NoSQL databases, and the Key-Value stores looks interresting. When I store geometric object I mostly use five indexed ...
19
votes
8answers
6k views

What are the best databases for storing spatial data? Pros and Cons

A couple of days ago I installed the demo of spatialware 4.9 from MapInfo into my SQL Server 2005 install and loaded all the larger dataset into it. I was quite impressed with the performance vs the ...
18
votes
7answers
1k views

Spatial databases learning resources for newbies

Would be taking up a course on spatial databases next semester. Would anybody know a newbie friendly introductory resource? A vendor neutral one would be preferable. Thanks.
17
votes
2answers
353 views

(When) should I use a GIS-enabled database?

I am a long-time programmer, new to GIS. I am trying to get a feel for the database aspects of GIS and I understand that there are some databases which are specialized for GIS use. Basically I am ...
15
votes
3answers
2k views

Database for offline slippy map tiles

I currently have an offline HTML5 map application (built on Leaflet & KendoUI with custom additions) that has an app manifest and works fine on multiple platforms. However, I am hesitant to use ...
13
votes
10answers
15k views

Where can I obtain an up-to-date list of US ZIP Codes with Latitude and Longitude Geocodes?

NOTE: This began as a question on Stack Overflow, which has subsequently been closed. I also noticed a similar question about Most Up-To-Date Source for US Zip Code Boundaries, but I believe this ...
13
votes
4answers
980 views

Database design: road topology in GIS

Is there a standard or a best practice way to store certain features about roads: Road directionality: One way streets: Roads going in one direction only Center Turning lanes: roads that exist ...
12
votes
2answers
545 views

Need a spatial database that can be used by QGIS and R

I'm quite new to QGIS and I'm searching for a simple way to create a Database that allows me to use the tables in QGIS and R. I have a lot of data stored in Excel spreadsheets wich will be used for ...
11
votes
5answers
317 views

Why do most GIS packages need a numeric id?

This is a simple yet possibly controversial question: why do most (if not all) GIS packages require that a determined layer have a unique not nullable numeric identifier? Why there is the need for ...
11
votes
3answers
8k views

What is the difference between FID and OID

What is the main difference between OID and FID in ESRI software?
11
votes
3answers
1k views

What is a good taxonomy or naming convention for files and folders containing GIS data?

My company has collected about 30 TBs of GIS data over the past 8 years, and I always find myself asking the following questions: What type of data do we have for a given geographic area? What are ...
11
votes
1answer
203 views

Naming conventions PostGIS Database

We are starting to build up a database with PostGIS. The database is supposed to be for a team of about 5-8 researches who work frequently with geodata and statistics. Has anybody experience with ...
10
votes
5answers
563 views

Database versus Files for Solo Developer

I'm just getting started in GIS and am interested in using it to create maps of mountain biking trails in my area and nearby. I've been learning QGIS and have made enough progress to generate a decent ...
10
votes
3answers
438 views

How can I handle tables with 256+ variables?

I'm working with census data and downloaded several CSV files, each with with 600ish columns/variables. I'd like to store them all in a query-able database, but everything I've tried so far (MS ...
10
votes
4answers
783 views

Open Street Map and PostgreSQL what do I exactly need?

I make my first steps in the GIS world and everything is very new for me even if I work on a "huge" project (ie: for a single programmer) very related to maps. My project needs to know informations ...
9
votes
2answers
296 views

How do you protect your PostGIS credentials when using QGIS 1.7?

I'm fairly certain this should be a community wiki, but I don't know how to make it one. So if an admin sees this please change if appropriate. So.....How do you protect your PostGIS database data ...
9
votes
2answers
887 views

How to design a Spatial Database for temporal Data?

I am working on a Weather based GIS App. I have the data from several weather stations, and this data will updated daily (by a web service). The obstacles I am facing are: There are currently 40 ...
9
votes
2answers
237 views

What is the best hack for importing large datasets into PostGIS?

I have to import large Shapefiles (> 1 million records) into PostGIS, and I have been wondering about the best way to do it. In my question I used the word "hack", instead of tool, on purpose ...
8
votes
4answers
3k views

ArcGIS fails to import all records from huge CSV file to file geodatabase table despite being within FGDB table size limits

I'm using ArcGIS 10.0 on Windows 7 64-bit with 4GB of RAM. I have some very large tables in CSV format to import to ArcGIS, they all have about 30 fields, upwards of 5 million records per table (a ...
8
votes
4answers
543 views

Geolocation database of beaches

Anyone know where or how to obtain a database of worldwide beaches? Required fields are: name latitude longitude coastline aspect (if possible) Alternatively, is there a way to query Google Maps ...
8
votes
2answers
1k views

Converting ms-access database into easy to use spatial database

I've recently come into ownership of an MS-Access database (2007 accdb), which I want to be able to use in a GIS. I know a little bit about GIS (I've used QGIS and ArcGIS quite a bit) but very little ...
8
votes
2answers
355 views

How can I find the median column in a database?

I have data on period of construction for dwellings in dissemination areas. I have transferred this data to my study areas and would like to determine the median period of construction for each study ...
8
votes
2answers
844 views

Future for geospatial on App Engine?

2 years ago, this question was posted here at Gillies's blog, on date of 2009-05-15. Future for geospatial on App Engine? At that time there was no news relating to any apps of GIS web services ...
8
votes
3answers
747 views

How to design a bus station query database schema?

We have bus station data, and we want to build an application which will provide the line/multiple line for a given start station and the end station. For example user try to get a bus line ...
8
votes
3answers
926 views

How to fix “Unable to initialize ODBC connection to DSN for ALC_AV_CO”?

So I am new to the QGIS community, and I have been trying to bring in some rather large access databases with little to no success. I have windows 7, so I've gone in through administrative tools/Data ...
8
votes
2answers
648 views

What are the Pros and Cons of hstore data type in postgis?

PostgreSQL has a module named hstore that implement the use of key/value pairs (it's something like the OpenStreetMap model, but in a single table). What are the Pros and Cons of hstore regarding GIS ...
7
votes
3answers
1k views

Suggestion about the database to be used with OpenLayers

Can anyone suggest me which database to be used with OpenLayers? I have to store the values in a DB table and retrieve them (trivial tasks). which is better MySQL or PostGIS? Can anybody give benefits ...
7
votes
6answers
2k views

I'm looking for a comprehensive database of all cities/towns in South Africa

The title says it all really - I'm looking for a comprehensive list/database of all cities/towns in South Africa. I know about these guys: http://www.afrigis.co.za/, but they're just not getting back ...
7
votes
2answers
277 views

Basics about Spatial Indexes

I was asking on a forum if it could be a good idea to create spatial indexes on subsets of a table when your application display on map only those subsets and never the entire table. I was asking ...
7
votes
2answers
441 views

How to create something similar to GDB in QGIS?

I used to work with ArcGIS. There I had geodatabases in which I could store several shapefiles with defined layer styles. Is there a way to do something similar with QGIS? The background is: we are ...
7
votes
2answers
3k views

QGIS supported databases?

Does anyone know if there is some kind of documentation on which database types that you can connect to in QGIS? I would also like to know if: Can I use the databes for read only or read & write. ...
7
votes
1answer
1k views

Why is my XY Event Source layer only displaying at full extent?

My XY Event Source layer is only displaying at full extent and when I zoom in, the features disappear. If I select a feature in the attribute table, the feature is highlighted. When I see this for a ...
6
votes
3answers
496 views

Suggestions for an efficient way to store raster files for lab use?

I'm trying to create a repository for our raster files from various sources and Im exploring the possibilities on how to store them and deliver them in our local intranet. I have come across rasdaman ...
6
votes
2answers
209 views

What technology is used behind arcpy cursors?

I'm using ArcGIS Server 10.0. I have a geoprocessing using arcpy search, update and insert cursors. I'd like to know more about the technology behind these cursors. Does it use any driver or pool to ...
6
votes
1answer
582 views

Data visualization and maintenance tool

Background Looking to leverage an existing GIS system for exploring organizational data. Architecture The following figure represents a high-level overview of the system's desired features: The ...
6
votes
2answers
691 views

GIS Database Migration Project (Oracle to ArcGIS)

I have been tasked with converting an Oracle Database into an ESRI file geodatabase. The data represents a gas network. The client's Oracle database has over 400 tables, 120 of which are spatial. ...
6
votes
2answers
633 views

Imagery Database/Metadata Store

I'm a Remote Sensing PhD student, and as such I have a large number of satellite images that I'm working with. I'm starting to fail to keep track of them all and I have a lot of metadata that I want ...
5
votes
2answers
2k views

Data organization strategies for .csv and .shp

I'm organizing a large amount of data for a project and the data is stored in .csv format, with a code to relate each row to a polygon in a .shp. I was planning on converting the .csv data into .dbf ...
5
votes
1answer
385 views

GIS-based reporting and maintenance tool

Background Conceptually, I am looking for a tool, or suite of software tools that can be readily integrated to help browse data using a GIS-based map (such as Google Maps). The proposed architecture ...
5
votes
1answer
355 views

How many kinds of “address” are there? [closed]

I'm defining "address" as "a physical location, usually visibly numbered". Numbered was used in the definition to exclude purely geographical features not usually considered to have or need an ...
5
votes
2answers
387 views

Who knows GIS based Customer Relationships Management (CRM) tools?

I'm searching for a tool like something around a "GIS based Customer Relationships Management Tool". The functionality I am looking for is: 1) collect: collecting customer related data in several ...
5
votes
1answer
1k views

ARCMAP ERROR 000464: Cannot get exclusive schema lock

I am trying to run the "Near" tool in Arcmap. Both my layers involved are on a SDE database. When I run the tool I get the following error... ERROR 000464: Cannot get exclusive schema lock. ...
4
votes
3answers
3k views

Is there a way to link ArcGIS to MS Access and use that DB?

I have an IT background but I am new to GIS. I recently recieved training using ARCMAP. I have about 5000 farmers that I need to put in a database and access the information using GIS. The vision is ...
4
votes
3answers
351 views

Looking for good resources for batch files in relation to databases/geodatabases

I hesitated a bit before asking this, as it isn't necessarily a GIS specific question, though I'm using it to update geodatabases. I have found plenty of hits on a Google search, but frankly, many of ...
4
votes
3answers
6k views

How to import info from mdb file?

I need to import info on a QGIS project. The info are in a MDB file (population, mean age, number cars and so on per Town) that is possible to connect with a region shape from an ID (the ID is the ...
4
votes
2answers
1k views

Is there a way to quickly reduce precision in a number of DOUBLE fields?

I was wondering if there is a way to reduce the precision for display of a DOUBLE field of a number of fields, in a shapefile. I have 25 fields and would like to do it as automatically as possible but ...
4
votes
3answers
501 views

QGIS, Postgis: Geometry type does not match column type

I'm trying to import some polygon shapefiles to Postgis in QGIS via SPIT. One of them can't be imported and returns this error: ERROR: Geometry type (Polygon) does not match column type ...
4
votes
1answer
179 views

Extract points from regular data.frame with coordinates based on SpatialPolygonsDataFrame in R

I have a regular data.frame called datos.merged class(datosmerged) [1] "data.frame" The last two columns are the corresponding geographical coordinates datosmerged[1,c(23,24)] XCOORD ...