Chapter 17. Representing Entities in Form Design
We've been concentrating so hard on work processes in the last few chapters that you might be wondering why you did all that data modeling. Never fear, in this chapter, we'll look at how to structure individual forms based on the way the entities displayed on them are represented in the data model. Your decisions about what data to include on any given form are based on work processes, but having made those decisions, the form layout and choice of controls will be determined by the actual data structures the forms represent.
The first decision you must make is how a form maps to the Entity Relationship (E/R) model. Does this form represent a single entity, two entities in a one-to-one relationship, two entities in a one-to-many relationship, or more than two entities? Each of these entity structures lends itself to certain kinds of form layouts, which we'll look at in this chapter. Of course, just like the architectures we explored in Chapter 16, these layouts are only general guidelines, not rules. These are the layouts that, in my experience, most naturally fit certain types of data structures.