Visual Basic provides us with the ability to create a range of components that are useful in the reporting process. Figure 3-4 on the next page displays some of the possible roles the various components can play in generating reports with Office 95 and Visual Basic 5. Microsoft Access is included in the business object layer because of the ease with which it can manipulate data objects (for example, a view on Microsoft SQL Server that represents business information). Reports or queries in Access can then be used to extract information from the data object and put it into a range of report output formats, normally Access reports.
Compare the lines between the control layer and the output medium layer in Figure 3-4 and in Figure 3-5. Figure 3-5 represents an improvement in integration between components, the result of common integration of ActiveX components in Office 97.
Figure 3-4 Using ActiveX components for reporting in Office 95
Figure 3-5 Using ActiveX components for reporting in Office 97
You might wonder why Microsoft Access is excluded from the control layer given that it is just as capable as Visual Basic 5 of producing report results. It’s because Access requires considerable memory and computer resources to run even the most basic application. This penalty isn’t worth it when only a few Access features will be used in the implementation of a control layer.