Datasheet

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Part I ✦ The Fundamentals
Limitations of paper databases
First, consider some of the shortcomings of paper databases:
✦ Making data-entry errors is easy to do. Even when you’re using a typeset form,
nothing prevents you from entering the wrong data in a field or forgetting to
fill in a critical field, such as the hire date or medical history.
✦ Maintenance can be difficult. For records to be easy to locate, they must be in
some rational order. Whenever you return or add a record to a folder or the
filing cabinet, you must place it in the correct spot. If you put the vendor file
for Alpha Corporation in the Q folder, you might never find it again!
✦ Updating records can be time-consuming. Because of changes in information
(such as addresses, phone numbers, and salaries), few databases are static.
Updating a paper record could require several steps, including finding the
record, erasing the old information, writing in the new information (or typing
a whole new record), and returning the form to the filing cabinet. Making an
across-the-board change — such as granting an incremental salary increase to
all employees — can take a long time.
✦ Sorting records, selecting subgroups of records, and creating reports are cumber-
some tasks. Suppose the boss walks into your office and says, “We’re thinking
about putting in a day-care center. How many of our 149 employees have kids
under the age of five?” Or you might be thinking of sending a direct mail piece
to your local customers. To determine printing and postage costs, you must
know how many customers are in the target ZIP code or are within a particu-
lar range of ZIP codes.
In either case, you probably have to examine every record in the paper data-
base. Whenever a task requires sorting, organizing, or summarizing the data
in a different way, you can look forward to a nightmare of paper shuffling —
hoping that you didn’t overlook something important. And when you’re
through, you have to restore all the records to their original order.
✦ Sharing records is difficult. When a supervisor borrows some employee records,
for example, the office manager no longer has easy access to those records
unless you decide to kill some trees by photocopying the paperwork. (They’re
no longer in the file drawer.)
✦ Information is hard to reuse. If you want to use the information in a paper
database for any purpose other than just reading it (addressing envelopes, for
example), someone has to drag out the typewriter. Photocopying an address
and then taping it onto a letter is considered bad form (unless you’re creating
a ransom note).
Advantages of computer databases
Computer databases, on the other hand, offer the following benefits:
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