This feature first appeared in the Spring 2019 issue of Certification Magazine. Click here to get your own print or digital copy.
Data has become an important part of nearly everything. In the United States, individuals are added to various databases at birth — to receive a birth certificate, to get a Social Security Number, to track immunization information — and the trove of data that identifies each of us only grows from there. Increasingly powerful technology is required to store, manage, access, and analyze all of that data.
Databases, one of the most basic building blocks of Big Data technology, are an integral and often invisible constituent element of our modern society. They're so ubiquitous that it's easy to forget how often we deal with them. Let's look at a typical Friday evening and count the databases encountered along the way:
At 5:00 p.m., you leave work after clocking out using your company's timekeeping software (1) and drive home. On the way, you stop by the grocery store. You scan each of your items using the self-checkout stand (2), swipe your loyalty card (3), and pay with your debit card (4). On the way out of the store, you decide to grab a movie from a DVD rental kiosk (5).
Instead of cooking dinner after you get home, you decide to visit your favorite pizza chain's website, place an order from their online menu (6), and pay with your credit card (7). In the course of an hour or two, you seamlessly used seven different databases and probably didn't think twice about any of them.
Since the world around you is so full of databases, understanding how they work is a valuable skill. For this reason, the Microsoft Access chapter of Desktop Pro, TestOut's Microsoft Office Specialist courseware, has a slightly different purpose than the chapters on Word, Excel and PowerPoint. Instead of focusing primarily on the software itself, Office Pro uses Access as a vehicle for teaching students how databases work.
The Access chapter of Desktop Pro helps students learn and understand features that are common to nearly all databases, such as the following:
Primary Key. Every person, item, or event in a database has a unique identifier attached to it called the primary key. This can be a number, a username, or a code. Primary keys are essential for a database to distinguish between similar records. For example, there are many people named Steve Decker. To tell them apart, the U.S. government uses Social Security numbers unique to each individual.
Tables. Tables form the foundation of any database. Each table contains several fields, which store a specific kind of information. For example, a table of cars would contain fields for the make, model, year, and color. Each item stored on a table is a record. Each individual car on the table would be its own record. (Incidentally, all cars have a unique VIN which is, of course, also a primary key.)
Relationships. Databases typically store different kinds of information on different tables. IMDb, an online movie database, has different behind-the-scenes tables for movies, actors, directors, and producers. By using relationships between the tables, the database keeps track of which actors and directors worked on each movie.
Have you ever played the party game Six Degrees of Kevin Bacon? Players try to connect any actor to Kevin Bacon through a series of other actors (using six or fewer links) by naming a movie each actor has in common with the next actor in the chain. You're essentially stating a string of relationships to connect whichever actor is chosen for the game to Mr. Bacon.
Queries. Queries are powerful tools for getting information out of a database. Each table can store thousands of records, and data is usually stored on multiple tables. Queries narrow down the database to only the information you want to see. For example, a school enrollment database can use a query to show only the teacher and students for a specific classroom.
Forms. Most database end users will never interface directly with tables and queries. Instead, they use forms to enter and search for data. If you've ever bought something online and submitted your name, address, and credit card number, then you've used a database form.
Reports. Reports are a visually appealing way to present data extracted from a database. If you're browsing a movie rental kiosk and ask to see all of the comedies (which you'll do by using a form), the kiosk will run a behind-the-scenes query of the movie data in its tables, and then present the information (the list of comedies) as a report.
Students who complete Desktop Pro will be able to create desktop databases in Access. More importantly, however, they will gain a conceptual understanding of how databases work in the real world — an increasingly valuable skill.