Understanding Access s Approach to Application Design

Understanding Access's Approach to Application Design

Unlike other members of Microsoft Office System 2003, Access 2003 requires that you build an application to take advantage of the product's power as a database development platform. Word 2003 and Excel 2003 let you automate simple repetitive operations by recording Visual Basic for Applications (VBA) macros. Access 2003 supports a set of macro commands for compatibility with previous versions, but Access macros don't use VBA. Access doesn't capture your mouse clicks and keystrokes and turn them into a series of macro commands or VBA code. It's up to you to design and implement the Access applications you need for your database projects.

A full-scale Access application involves at least the following three basic Access object types:

• Tables that store the data you or others add to the database

• Forms for displaying and entering data, controlling the opening and closing of other forms, and printing reports

• Reports to print detail information, summary information, or both in tables

Most Access applications also use queries to filter, sort, and combine your data, and modules to store VBA code. Access 2003 forms can (and usually do) contain VBA code in a special type of module, called a Class Module. All objects that make up your application are stored in a container called a Database object, which is a single file with an .mdb extension, such as Northwind.mdb. Access is unique in that it can store an entire database application in a single file. Other desktop databases, such as Microsoft FoxPro, require multiple files to store their objects.

New Access users often find it difficult to "get a grip" on how to start developing a self-contained database application. Dealing with an unfamiliar set of objects tends to intimidate first-time database developers. Fortunately, Microsoft includes with Access 2003 various wizards that guide you, step by step, through complex tasks. One of the most accomplished of the Access wizards is the Database Wizard that creates a typical Access 2003 "starter" application from a set of prefabricated database templates. In this chapter, you use the Database Wizard to create a relatively simple but useful Contact Manager application. Then you explore the objects generated by the Wizard to gain perspective on the relationship of Access objects and learn how they're integrated within a typical Access database application.

If you're upgrading from Access 97 to 2003, the following features introduced by Access 2000 and 2002 are discussed in this chapter:

• Subdatasheets, which open when you click a plus sign to the left of the first field in Table Datasheet view. Subdatasheets automatically display records of another table that's related to the current table.

• Visual Basic for Applications code editor, which Access 2003 shares with other Office 2003 applications. Access 97 and earlier used its own VBA editing window for code modules.

• Data access pages (DAP), which Access 2000 introduced and Access 2002 made practical for intranet or Internet deployment.