Using Data BASES
Date: 2015-10-07; view: 456.
Read the text and get ready to dive a characteristics to the data – base and explain its usage. in practical activities.
Give their Ukrainian equivalents.
Read the following word – combination and pay attention to their meaning.
Lets go back; as you know; some such as; most of ten; by others; differ from one another; both content and format; the more …. the more likely it is; the more … the easier.
Imagine getting the information you need by simply entering a command or type on your .computer keyboard. Many people do this. They use data-base management systems— special software developed for record keeping — to create electronic files. Then the computer does all the work of computer does all the work of sorting through the files to retrieve specific information. Sound intriguing? This chapter will give you an idea of how and why you might put a data-base management system to work for you. You will also learn how to evaluate and select the data-base management software program that will best serve your specific needs.
Before explaining exactly what a data base management system is and how it works, let's go back to the concept of a data base. Data, as youknow, are facts or figures. A data base is a source of facts and figures a collection of related information.
You already are familiar with many data bases. Some such as baseball card collection, are ones you developed yourself. But the data bases you use most often have probably been created by others. Can you name some of these? A telephone directory is a data base. So is a dictionary and a television program guide. These collections all differ from one another in both content and format. But each is a data base simply because it is a source of information.
CHARACTERISTICS OFAGOOD DATABASE
A useful data base has four important characteristics.
The more complete a data base is, the more likely it is to have the information that you need. For example you'll find Dave Winfield's batting average only if you have his baseball card. You'll be able to check your friend Jan's telephone number only if you've listed it in your address book.
You might organize facts alphabetically, chronologically, or by topic. How you organize your data base depends on both its content and its intended use.
The more structured your data base is the easier it is to find information.