Opening Database Connections

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Attention: The Borland Database Engine (BDE) has been deprecated, so it will not be enhanced. For instance, BDE will never have Unicode support. You should not undertake new development with BDE. Consider migrating your existing database applications from BDE to dbExpress.

To open a database connection within a session, call the OpenDatabase method. OpenDatabase takes one parameter, the name of the database to open. This name is a BDE alias or the name of a database component. For Paradox or dBASE, the name can also be a fully qualified path name. For example, the following statement uses the default session and attempts to open a database connection for the database pointed to by the DBDEMOS alias:

var
  DBDemosDatabase: TDatabase;
begin
  DBDemosDatabase := Session.OpenDatabase('DBDEMOS');
  ...

TDatabase *BCDemosDatabase = Session->OpenDatabase("BCDEMOS");

OpenDatabase actives the session if it is not already active, and then checks whether the specified database name matches the DatabaseName property of any database components for the session. If the name does not match an existing database component, OpenDatabase creates a temporary database component using the specified name. Finally, OpenDatabase calls the Open method of the database component to connect to the server. Each call to OpenDatabase increments a reference count for the database by 1. As long as this reference count remains greater than 0, the database is open.

See Also

• Closing Database Connections
• Dropping Temporary Database Connections
• Iterating Through a Session's Database Components
• Searching for a Database Connection