Some basic definitions, mostly that I've run across and am only vaguely familiar with.
SQL (Structured Query Language) (pronounced /ˌɛs.kjuːˈɛl/ ES-kyoo-EL )[1][2] is a database computer language designed for managing data in relational database management systems (RDBMS), and originally based upon Relational Algebra. Its scope includes data query and update, schema creation and modification, and data access control.
This is something I touched on, very very lightly last semester. We did some incredibly basic SQL joins. All the query functions in GRASS are based on SQL. (Remember how I said I had absolutely no programming background?)
Map Projection: The projection of a map is incredibly important. Wrong projection programmed into your GIS and none of your coordinates are right. It took me a good 20 minutes or so to figure out that my data had NAD83 map info.
Here is the projection of my cities and state information for IL and whatnot. I could add labels. Everytime I tried to do the SQL query I screwed up though. Which means a trip to the library.. or book store, or browsing on the intarweb to find the info that I need to do what I want to.
At first I didn't zoom in enough to notice that my state had a state boundary, as well as a lake michigan boundary. The cities data is sorted by population, county, county seat, state, etc, and I was hoping to do a queary for JUST cities in IL. Its too late at night to learn new skills though, I think its an accomlishment that I even got anything projected! (which took me multiple attempts..)
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