Relational tables and spreadsheets look similar with both having rows and columns. What are some important differences between the two?
A relational table cannot have duplicate rows and must have unique identifying names, whereas a spreadsheet does not have these rules, as they can be distinguished by their absolute position on the sheet.
What are some important reasons for using a database rather than just using files?
Databases allow for greater usability because of SQL which is designed specifically to navigate and manipulate the database, rather than files which would require writing code in your program for this purpose. The orientation slides provide an example with the inner join and outer join actions, which can be used to navigate relationships such as students enrolled in a course.
An SQL select statements has SELECT, FROM, WHERE, ORDER BY, LIMIT parts. Which are optional and which are required?
In an SQL select statement, you must use the SELECT and FROM keywords, so that the software knows where to look and what to look for. Everything else in this list is optional and may not be used in some circumstances.