Database Application Design n Characteristics of Database Applications n Form Design n Report Design...
-
Upload
jared-powell -
Category
Documents
-
view
212 -
download
0
Transcript of Database Application Design n Characteristics of Database Applications n Form Design n Report Design...
Database Application Design
Characteristics of Database Applications
Form Design Report Design Application Program Design
Characteristics of Database Applications Object Materialization occurs when we
construct the objects using the underlying relations
Facilities for controlling processing include:– Commands– Menus– A Graphical User Interface
Characteristics of Database Applications (Cont.) An object view, or user view, is a named
subset of an object required by a specific user or user group.
Form Design
The form structure should reflect the object structure -> Fig. 8-8 and 8-2a
The semantics of the data should be graphically evident
The form structure should encourage appropriate action
Careful with cursor movement and pervasive keys
Form Design (Cont.)
Forms in a GUI environment may include: – Drop-Down List Boxes -> Fig. 8-9– Option or Radio Buttons (only one
alternative can be selected) -> Fig. 8-11– Check Boxes (more than one alternatives
may be chosen) -> Fig. 8-12
Report Design
Report structure: should reflect the structure of the underlying object.
Implied Objects (Data sorting within a report) -> Fig. 8-13, 14– Sorting by object identifier– Sorting by nonidentifier, nonobject columns– Sorting by attributes contained in object
attributes
Application Program Design
Designing the structure of application logic: Pseudocode or other technique
Relationship constraint checking– Fragments: A row in a table which exists
inappropriately without the required parent or child
– Orphans: Child rows that exist without a mandatory parent
Application Program Design (Cont.)
– Types of relationship constraint: • Mandatory to mandatory• Mandatory to optional• Optional to optional
– Restrictions on updates -> Fig. 8-18 Other types of constraint checking e.g.
uniqueness