Newbie GIS question - how to map a custom dataset

I have searched, believe me, I have searched!

But I can't find exactly how everything glues together.

Could someone please give me an overview of how a GIS works, from a development perspective?

I understand the concepts behind rasters, layers, spatial data, geometries etc, but what I don't understand at all are the basics of how it comes together:

• A SQL 2008 database will hold our spatially-aware dataset. How does the data get into here in the first place?
• Say I want to query that data and display it. A lot of GIS software talks about "Shape Files". I understand that I would load a base shape file, but then I want to colour different regions of the map according to data in my database. How would this happen?
• Where do you get the rasters and shape files in the first place? The co-ordinate system has to be shared, which ties in with my first point, how does this normally happen?

The vision is to have a web site that uses an off the shelf GIS component suite to de开发者_如何学Cliver this functionality, but I don't know how to integrate this with my custom data sets?

Apologies as I know this is quite a vague question, but I'd really appreciate some guidance on the above, even at quite a high level Thanks

• I don't know about SQL 2008, but Postgress, MySQL, Sqlite etc all have extensions for spatially-aware data that can load and store "Shape Files" and various other formats.
• "Shape Files" is ESRI ShapeFile. It's kind of common format for exchanging maps, though it's pretty inefficient when it comes to working with it. Most GIS tools can work with those plus each has a few other, often more efficient formats.
• You either buy digital maps somewhere (vector ones usually come as shapefiles), get free ones (some very coarse data are available from NASA or there is OpenStreetMap, though that uses it's own rather vague format, so it'll take some work to import, or create them yourself, using either free (e.g. QGis) or proprietary GIS software.
• Except for legacy reasons, coordinate system is almost always WGS84, which is the common longitude and latitude angles with sufficiently precisely specified reference frame. If it's not, there is the proj library that can convert data given in various cartographic projections (since paper maps are flat, they need to use some projection; when digitizing them, you end up with data in that projection) to WGS84 or each other (advanced GIS tools will have such conversions built in, too).

This is a vendor-specific answer that might be useful. The concepts are generally helpful even if the software itself is not for you. Manifold has very good support for data in SQL Server, dynamic query-based presentations and "shared" coordinate systems for multiple layer maps.

General overview:

http://www.georeference.org/doc/introduction.htm

Key GIS concepts:

http://www.georeference.org/doc/key_ideas_in_gis.htm

Overview of vector and raster layers in maps:

http://www.georeference.org/doc/drawings_images_and_maps.htm