Access Database Design and Programming, Second Edition

The Jet DBMS

As the title of the book suggests, our primary interest is in the DBMS that underlies Microsoft Access (and also Visual Basic). Accordingly, we will take our examples from this DBMS, called the Jet DBMS or the Jet Database Engine. The relationship between the Jet DBMS and other database-related programs, including Microsoft Access and Visual Basic, can be pictured as in Figure 7.2.

Figure 7-2. The relationships and structure of the Jet Database Engine (DBMS)

Microsoft’s application-level products Visual Basic, Access, and Excel play host to Visual Basic for Applications (or VBA), which is the underlying programming language (also called scripting or macro language) for these applications. (Microsoft Word Version 7 does not use VBA—it uses a similar language called Word Basic. However, as of Microsoft Word 97, Word does use VBA.) As expected, each of these applications integrates VBA into its environment in a specific way, since each application has a different purpose.

In turn, Visual Basic for Applications is the host language for the Jet DBMS. The Jet DBMS contains the Data Access Object component (or DAO), which is the programming language interface for the Jet DBMS. The DAO provides a more-or-less object-oriented DDL and DML, thereby allowing the VBA programmer to define the structure of a database and manipulate its data.

The Jet Database Engine is a collection of ...