A new problem that has evolved with the use of personal productivity tools (such as spreadsheet and desktop databases)
is that users typically lack proper design and data-modeling skills. People naturally have an integrated view of the
data in their environment. For example, consider a student’s class schedule. The schedule probably contains the student’s
identification number and name, class code, class description, class credit hours, class instructor name, the class
meeting days and times, and the class room number. In the mind of the student, these various data items compose a
single unit. If a student organization wanted to keep a record of the schedules of its members, an end user might make
a spreadsheet to store the schedule information. Even if the student makes a foray into the realm of desktop databases,
he or she is likely to create a structure composed of a single table that mimics the schedule structure. As you will learn
in the coming chapters, forcing this type of integrated data into a single two-dimensional table structure is a poor data
design that leads to a large degree of redundancy for several data items.
A new problem that has evolved with the use of personal productivity tools (such as spreadsheet and desktop databases)
is that users typically lack proper design and data-modeling skills. People naturally have an integrated view of the
data in their environment. For example, consider a student’s class schedule. The schedule probably contains the student’s
identification number and name, class code, class description, class credit hours, class instructor name, the class
meeting days and times, and the class room number. In the mind of the student, these various data items compose a
single unit. If a student organization wanted to keep a record of the schedules of its members, an end user might make
a spreadsheet to store the schedule information. Even if the student makes a foray into the realm of desktop databases,
he or she is likely to create a structure composed of a single table that mimics the schedule structure. As you will learn
in the coming chapters, forcing this type of integrated data into a single two-dimensional table structure is a poor data
design that leads to a large degree of redundancy for several data items.
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