Extending Database Files
Each .dbc file contains a Memo field named User that you can use to store your own information about each record in the database. You can also extend a .dbc file to add fields to accommodate your own needs as a developer. Fields must be added to the end of the structure. You must have exclusive access to a .dbc file to modify its structure.
To add a field to a .dbc file
- Open the .dbc file for exclusive use with the USE command.
- Use the MODIFY STRUCTURE command.
For example, the following code opens the Table Designer so you can add a field to the structure of Testdata.dbc:
USE TESTDATA.DBC EXCLUSIVE
MODIFY STRUCTURE
When you add a new field to a database file, begin the field name with "U" to designate it as a user-defined field. This designation prevents your field from conflicting with any future extensions to the .dbc file.
Caution Don't change any existing Visual FoxPro- defined fields in a .dbc file. Any changes you make to a .dbc file could affect the integrity of your database.
See Also
Viewing and Modifying Database Architecture | Validating a Database | Managing a Database | Creating Databases | Referencing Multiple Databases | Working with a Database