CS 325 - Week 2 Lecture 1 - 2016-08-30

*   informal definition of a database -
    a database is collection of tables,
    holding information about different
    interrelated entities

*   an entity class is a collection of things
    important in a world or scenario --
    we'll eventually see that an entity class is
    eventually represented by one OR MORE
    tables in an eventual database

*   DBMS - Database Management System
    *   a collection of programs that acts as the
        interface between a 
        user-or-application-program and a database

*   a little history...
    *   there's file as a stream of characters
    *   BUT, in older business information
        systems,
	there's file as a collection of records,
	where each record is a collection of fields,
	and each field is one or more characters

    *   there are classic problems that come
        up as you store more and more data
	about more and more things in
	files (in file-processing systems)

        *   separated and isolated data
        *   (unnecessary) data duplication
        *   application program dependency
        *   incompatible files
        *   difficulty of representing data
	    in the users' perspective
	    (especially in an ad-hoc sense)