TB_ADO28 v. 1.1

ADO, ADOX and JRO Wrapper Functions

Microsoft® ActiveX® Data Objects (ADO) enable your client applications to access and manipulate data from a variety of sources through an OLE DB provider. Its primary benefits are ease of use, high speed, low memory overhead, and a small disk footprint. ADO supports key features for building client/server and Web-based applications.

Microsoft® ActiveX® Data Objects Extensions for Data Definition Language and Security (ADOX) is an extension to the ADO objects and programming model. ADOX includes objects for schema creation and modification, as well as security. Because it is an object-based approach to schema manipulation, you can write code that will work against various data sources regardless of differences in their native syntaxes.

ADOX is a companion library to the core ADO objects. It exposes additional objects for creating, modifying, and deleting schema objects, such as tables and procedures. It also includes security objects to maintain users and groups and to grant and revoke permissions on objects.

Jet and Replication Objects (JRO) is a set of automation interfaces that allow you to perform actions specific to Microsoft Jet databases. Using Jet and Replication Objects, you can compact databases, refresh data from the cache, and create and maintain replicated databases.

TB_ADO28.DLL is a collection of wrapper functions that allow you to use these components in procedural form with PowerBASIC Compiler for Windows 7.0+ or PowerBASIC Console Compiler 3.0+.

Handling Ado Events

The ADO event model supports certain synchronous and asynchronous ADO operations that issue events, or notifications, before the operation starts or after it completes. An event is actually a call to an event-handler routine that you define in your application.

If you provide handler functions or procedures for the group of events that occur before the operation starts, you can examine or modify the parameters that were passed to the operation. Because it has not been executed yet, you can either cancel the operation or allow it to complete.

The group of events that occur after an operation completes are especially important if you use ADO asynchronously. For example, an application that starts an asynchronous Recordset.Open operation is notified by an execution complete event when the operation concludes.

Using the ADO event model adds some overhead to your application but provides far more flexibility than other methods of dealing with asynchronous operations, such as monitoring the State property of an object with a loop.

The file AdoEvents.inc includes two classes to allow you to connect and disconnect to the events fired by a connection or recordset.

Disclaimer

This software and accompanying documentation are provided "as is" and without warranties as to performance or merchantability or any other warranties whether expressed or implied. Because of the various hardware and software environments into which this application may be used, no warranty of fitness for a particular purpose is offered. The user must assume the entire risk of using this software. In no case shall any of the contributors to this project be liable for any incidental, special or consequential damages or loss, including, without limitation, lost profits or the inability to use equipment or access data. This is true even if we are advised of the possibility of such damages. We also don't have any obligation of' fix eventual bugs or to add new features.

What is new in this version?

® The only change made to this version is that now the error code returned if you pass a null pointer as the value of the pthis parameter will be %E_POINTER instead of -1. This way, FormatMessage will return a localized description.

Downloads

TB_ADO28.ZIP (292 Kb) (26 Oct 2005)

® Includes DLL, headers, source code and examples

Page last updated on Saturday, 04 November 2006 00:16:45 +0100