Datasheet

WARNING It is important to remember that Access does not let go of disk
space on its own. This means that as time goes on, all the file space taken up
by the data you imported will be held by your Access file, regardless of whether
or not the data is still there. With that in mind, it is critical that you “compact
and repair” your Access database regularly to ensure that your database does
not grow to an unmanageable size, or even worse, become corrupted. To
compact and repair your database, simply select Tools → Database Utilities →
Compact and Repair Database.
Importing data from Excel spreadsheets
You can import data from a wide variety of sources into Access tables: Excel
spreadsheets, text files, or another database table. Access provides a set of
easy-to-use Import wizards, such as the one illustrated in Figure 1-10, that
guide you through the process of importing data.
If you are importing a properly formatted Excel flat file, the wizard prompts
you to ask if the top line is the location of the column names. Another
extremely useful feature of this wizard is that it lets you select a column to
serve as the primary key of the table or it will add an AutoNumber primary
key. If you select a column to serve as the primary key, the wizard performs a
test on the column to ensure against duplicate values. If duplicate values exist
in that column, the wizard informs you that it cannot set that column as the
primary key and the table is imported anyway.
Figure 1-10 The Import Spreadsheet Wizard displays
sample data from the worksheet selected in the display.
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