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Training Newsletter
Mosaic Media
Working Smarter with Microsoft Access – "It Pays to Know Your Data Types"
Computer users have tried all kinds of methods – books, tapes, interactive CDs – to learn software programs. A four-page biweekly newsletter may not seem the most likely training medium, but it has distinct advantages. Each issue of the Working Smarter with Microsoft Access letter, which I wrote from 1998-2000, included articles, Q&As, quizzes, quick tips, tutorials, and a cartoon. These small doses of database help are a great way to help busy employees improve their Access skills in a fun, no-pressure atmosphere.
For sample newsletter please download ACCESS.pdf (153 KB)
It Pays to Know Your Data Types
You don't add up ZIP Codes and you don't alphabetize prices: each kind of data has its own specific purpose, and each can be manipulated in specific ways. When you create a new table, you assign each field a data type that helps define its function and format. Selecting the right data types is critical for using database information.
You choose data types in the Table design view. To view them, open any table in Design view. In the top pane, click in any cell in the Data Type column and click the drop-down arrow.
Easy choices
A date field – l/l/99; June 15, 1987 – takes the Date/Time data type. And Currency is the choice for monetary values such as prices. Text is also fairly straightforward: it's the data type for any combination of alphanumeric characters. So Text is the choice for names as well as addresses, which use both numbers and letters. Text is your "when in doubt" choice.
Numbers
In Access, there are basically two types of numbers: those you use in calculations, and those you don't. The latter includes phone numbers and ZIP Codes. Fields that might be used in calculations include inventories, sales figures, discounts, and so on. It is these fields that take the Number data type. No dashes, letters, parentheses, or special characters are allowed.
Every time you add a record, Access increases the number in an AutoNumber field by one. An AutoNumber provides a unique number for each record. It's often designated as the primary key for the table.
Yes or no?
Some fields tell you whether or not something is true. Does a shipper provide next-day delivery? Is an organization nonprofit? You give these fields the Yes/No type. In a form or report, you can show Yes/No status graphically with a checkbox or option button.
Memo
A Text field is limited to 255 characters. When you need even more room – say, for an employee biography – use the Memo data type, which provides up to 64,000 characters. Note that you cannot index or sort a Memo field.
...and the others
In a field with the OLE Object data type, you store objects created in other programs (e.g., pictures and sounds) that are linked or embedded in the table. And with the Lookup Wizard, you choose a value from a list that can use as its source a field in another table. Watch for in-depth explorations of data types in future issues.
For sample newsletter please download ACCESS.pdf (153 KB)
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