Microsoft® SQL Server® 2012 Bible

143

CHAPTER

7

Relational Database Design and

Creating the Physical Database

Schema

IN THIS CHAPTER

Introducing Entities, Tuples, and Attributes

Understanding Conceptual Diagramming Versus SQL DDL

Avoiding Normalization Over-complexity

Choosing the Right Database Design Pattern

Ensuring Data Integrity

Exploring Alternative Patterns

Using Normal Forms

T

here are some musicians who can hear a song and then play it; most people don’t have that abil-

ity. Most can feel the rhythm, but have to work through the chords and fi gure them out almost

mathematically before they can play anything but a simple piece. To most, building chords and

chord progressions is like drawing geometric patterns on the guitar neck using the frets and strings.

Music theory encompasses the scales, chords, and progressions used to make music. Every melody,

harmony, rhythm, and song draws from music theory. For some musicians there’s just a feeling that

the song sounds right. For those who make music their profession, they understand the theory

behind why a song feels right. Great musicians have both the feel and the theory in their music.

Designing databases is similar to playing music. Databases are designed by combining the right pat-

terns to correctly model a specifi c solution to a problem. Normalization is the theory that shapes

the design. There’s both the mathematic theory of relational algebra and the intuitive feel of an

elegant database.

Designing databases is both science and art.

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