Microsoft SQL Server 2012 Bible

Summary

Smart database design, covered in Chapter 2, “Data Architecture,” showed why the database physical schema is critical to the database's performance. This chapter looked at the theory behind the logical correctness of the database design and the many patterns used to assemble a database schema.

• The three phases in database design are the conceptual (diagramming) phase, the SQL DDL (create table) phase, and the physical layer (partition and file location) phase. Databases designed with only the conceptual phase perform poorly.
• Normalization can be summed up as the three “Rules of One”: one group of items = one table; one item = one row; and one fact = one column.
• Generalization is the buffer against normalization over-complexity.