Objective: Learn how computer databases are organized and how to search them for information.
Background: A database is any collection of information that can be organized and sorted. Most computer databases contain information organized in the form of a table consisting of rows and columns. Each row in the table contains the information for an individual record. Each column contains information about a certain property of each record; these properties are often called fields. You can use as many fields as necessary to describe the properties of each record. For example, we can build a rock art database where the records are individual images for which we can specify properties or fields like how the image was made, what it represents, what color it is, and so on. You can also sort records and fields numerically, alphabetically or in other ways that you specify. Fields containing data entries that can be sorted in specified ways are called index fields. It is also possible to extend the information about records by linking multiple tables that contain different sets of fields. Many separate tables can be linked if pairs of tables share at least one field in common for each set of records. Databases constructed of multiple, linked tables are called relational databases.
Activity: Go to the Search screen of the Rock Art Database and perform at least three searches. For starters, click on Site Type = Shelters, Rock Art Category = Prehistoric Native American, Rock Art Type = Pictograph, General Motif = Anthropomorph. Your return screen will contain a list of images that fit your search specifications. Click on a few of these images to see what information was retrieved from the database. Repeat these procedures for at least two more searches for which you choose some different specifications. Note again the information categories that your searches return. Now see if you can answer the following questions:
- What is a database?
- What are the main components of a database?
- How are these components represented in the rock art database?
- What can you use a database for?
Additional Exercise: Pick a topic or subject for which you would like to create a simple database. Lay out a row-and-column table for the database in which you specify the kind of records you will store in the database and what fields will be used to describe each record. For index fields, indicate how you want to sort the information.
Contributed by: George Sabo III, Arkansas Archeological Survey