There are several ways to access data in the PowerBuilder development environment:
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Through one of the standard database interfaces such as ODBC, JDBC,ADO.NET, or OLE DB
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Through one of the native database interfaces
A standard database interface communicates with a database through a standard-compliant driver (in the case of ODBC and JDBC) or data provider (in the case of OLE DB and ADO.NET). 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 PowerBuilder Setup program.
PowerBuilder currently supports the following standard interfaces:
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Open Database Connectivity (ODBC)
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Java Database Connectivity (JDBC)
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Microsoft's Universal Data Access Component OLE DB
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Microsoft's ADO.NET
A native database interface communicates with a database through a direct connection. It communicates to a database using that database's native API.
To access data through one of the native database interfaces, you must first install the appropriate database software on the server and client workstations at your site. Then, install the native database interface that accesses your DBMS by selecting the interface in the PowerBuilder Setup program.
For example, if you have the appropriate SAP Adaptive Server Enterprise server and client software installed, you can access the database by installing the Adaptive Server Enterprise database interface.
Loading database interface libraries
PowerBuilder loads the libraries used by a database interface when it connects to the database. PowerBuilder 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 PowerBuilder to free database interface libraries on disconnecting from the database (as it did prior to PowerBuilder 8), you can change its default behavior:
To change the default behavior for |
Do this |
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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 |