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Part I: Laying the Foundations
In a chapter packed with ideas, the following are key take-aways:■ The database architect position should be equally involved in the enterprise-level
design and the project-level designs.
■ You can measure any database design or implementation using six database objec-
tives: usability, extensibility, data integrity, performance, availability, and secu-
rity. These objectives don’t need to compete — you can design an elegant database
that meets all six objectives.
■ Early investment in database design is worth it; it can save development and main-
tenance cost later.
■ Extensibility is the most expensive database objective to correct after the fact.
A database incapable of absorbing organizational changes and new requirements
elegantly will evolve into an unmaintainable mess. Smart Database Design is the
premise that an elegant physical schema makes the data intuitively obvious and
enables writing great set-based queries that respond well to indexing. This in turn
creates short, tight transactions, which improves concurrency and scalability while
reducing the aggregate workload of the database. This fl ow from layer to layer
becomes a methodology for designing and optimizing databases.
■ Reducing the aggregate workload of the database has a longer-term positive effect
than buying more hardware.
From this overview of data architecture, the next chapter digs deeper into the concepts and
patterns of relational database design, which are critical for usability, extensibility, data
integrity, and performance.c02.indd 30c02.indd 30 7/30/2012 4:07:54 PM7/30/2012 4:07:54 PM
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