FC-03 - Philosophical Perspectives
This entry follows in the footsteps of Anselin’s famous 1989 NCGIA working paper entitled “What is special about spatial?” (a report that is very timely again in an age when non-spatial data scientists are ignorant of the special characteristics of spatial data), where he outlines three unrelated but fundamental characteristics of spatial data. In a similar vein, I am going to discuss some philosophical perspectives that are internally unrelated to each other and could warrant individual entries in this Body of Knowledge. The first one is the notions of space and time and how they have evolved in philosophical discourse over the past three millennia. Related to these are aspects of absolute versus relative conceptions of these two fundamental constructs. The second is a brief introduction to key philosophical approaches and how they impact geospatial science and technology use today. The third is a discussion of which of the promises of the Quantitative Revolution in Geography and neighboring disciplines have been fulfilled by GIScience (and what is still missing). The fourth and final one is an introduction to the role that GIScience may play in what has recently been formalized as theory-guided data science.
FC-12 - Structured Query Language (SQL) and attribute queries
The structured query language (SQL) for database interrogation is presented and illustrated with a few examples using attribute tables one might find in a common GIS database. A short background is presented on the history and goals that the creators of the SQL language hoped to achieve, followed by a review of SQL utility for data query, editing, and definition. While the SQL language is rich in content and breadth, this article attempts to build on a simple SQL and then iteratively add additional complexity to highlight the power that SQL affords to the GIS professional who has limited programming capabilities. The reader is asked to consider how minor modifications to SQL syntax can add complexity and even create more dynamic mathematical models with simple English-like command statements. Finally, the reader is challenged to consider how terse SQL statements may be used to replace relatively long and laborious command sequences required by a GIS GUI approach.