As with most other things in life, tables sometimes need to change. You might have to modify field names, change data types, adjust field sizes, or add fields. Before you make any significant or extensive changes, be sure to back up your original tables.
TIP Access 2003 makes it easy to back up your database. In the Database window, choose File, Backup Database. In the Save Backup As dialog box, navigate to a convenient folder and save the file.
In earlier versions of Access, the surest way to wreak havoc on your database was to change a field name. For example, you might have edited the name of a field that was in one or more queries. Access would then be baffled about where to retrieve ...