About database interfaces

There are two ways to access data in the PocketBuilder development environment:

Through a standard database interface
Through a native database interface

Standard database interfaces

A standard database interface communicates with a database through a standard-compliant driver or data provider. The standard-compliant driver or data provider translates the abstract function calls defined by the standard’s API into calls that are understood by a specific database. To use a standard interface, you need to install the standard’s API and a suitable driver or data provider. Then, install the standard database interface you want to use to access your DBMS by selecting the interface in the PocketBuilder Setup program.

PocketBuilder currently supports the Open Database Connectivity (ODBC) standard driver.

Native database interfaces

A native database interface communicates with a database through a direct connection, using that database’s native API and a PocketBuilder database interface DLL for that specific database.

PocketBuilder currently provides a native interface to UltraLite 9.x databases through the file pkul920.dll. This file is installed by default when you install PocketBuilder.

Loading database interface libraries

PocketBuilder loads the libraries used by a database interface when it connects to the database. PocketBuilder does not automatically free the database interface libraries when it disconnects.

Although memory use is somewhat increased by this technique (since the loaded database interface libraries continue to be held in memory), the technique improves performance and eliminates problems associated with the freeing and subsequent reloading of libraries experienced by some database connections.

If you want PocketBuilder to free database interface libraries on disconnecting from the database, you can change its default behavior:

To change the default behavior for	Do this
Connections in the development environment	Select the Free Database Driver Libraries On Disconnect check box on the General tab of the System Options dialog box.
Runtime connections	Set the FreeDBLibraries property of the Application object to TRUE on the General tab of the Properties view in the Application painter or in a script.