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.
45
votes
7answers
1k 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 ...
31
votes
3answers
4k 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
3k 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 ...
18
votes
7answers
940 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.
16
votes
2answers
225 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
6answers
3k 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 ...
13
votes
3answers
725 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 ...
12
votes
9answers
5k 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 ...
12
votes
2answers
367 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 ...
12
votes
4answers
645 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 ...
11
votes
5answers
285 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
1answer
164 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
503 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
5k views
What is the difference between FID and OID
What is the main difference between OID and FID in ESRI software?
10
votes
3answers
328 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
3answers
866 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 ...
9
votes
2answers
217 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
4answers
616 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 ...
8
votes
4answers
260 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
630 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
222 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
679 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 ...
8
votes
2answers
580 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
1answer
366 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 ...
7
votes
3answers
937 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
5answers
775 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
226 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
2k 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
3answers
1k 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 ...
7
votes
2answers
469 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
1answer
954 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
1answer
354 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
418 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
3answers
180 views
Methods for lat/lon quality control?
I have a database with fields including latitude, longitude, city, state, and country.
When mapped, it is clear that a number of the sites are in the wrong location - most commonly because of a sign ...
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
2answers
87 views
Basics about Spatial Index
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 ...
5
votes
2answers
255 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 ...
5
votes
1answer
237 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
268 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
114 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 ...
4
votes
3answers
303 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
2answers
538 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
1k views
Delete a feature data set in SDE 10 programmatically
Is there a way to delete a feature data set and all of its feature classes programmatically either by using custom code or pre-existing command line tools?
There is a tool provided by SDE called ...
4
votes
2answers
280 views
Where can I find GeoJSON resources files?
I'm looking for demographic information and various things, and most of the time data are available as CSV (my application use geoJSON format).
Shall I encode the CSV to geoJSON or is there a ...
4
votes
2answers
192 views
Using a web map to identify and access data
I am trying to making a webpage where the user pans and zooms on a map, and based on the location and zoom level, some data is displayed on the webpage (drawn from another source). The data that will ...
4
votes
2answers
200 views
Calculate Field based on field value in a second table
I have a table in a MSSQL Server Enterprise SDE database. I need to join a table from a MS SQLExpress Workgroup SDE database and then calculate 11 fields in the Enterprise table based on values in ...
4
votes
1answer
303 views
SDE analysis - file locking logistics - ArcSDE 10 on MSSQL
I have a set of feature classes that I want to be able to edit schema or what ever I want to do in the heat of the battle and I don't want to be stiffled by schema locks.
I have a interpretable ...
4
votes
2answers
1k views
Arcpy Insert Cursor not inserting all rows
Good morning all, I have a script here that takes data from a cross-tabulated non-spatial dataset where monthly values are stored in a single table row for a given year and linearizes those data so ...
4
votes
1answer
163 views
Spatial index vs two coordinates indexes
I have a table with two columns: latitude and longitude. I want to get all objects inside a "rectangular" (well, rectangular in a lat/lon coordinate metric) bounding box: min-max latitude and min-max ...
4
votes
2answers
208 views
Fastest way to remove matched points
Hoping someone can see a faster way of doing this, because at the moment I'm averaging 9 hours per run for what I'm trying to do and well basically getting my behind chewed off by the boss :-)
The ...
