All the data objects you have learned about so far (entities, relationships, attributes, and entity occurrences) translate into SQL tables, joins between tables, columns, and rows. The tables, columns, and rows of your database must fit the rules found in Defining Tables, Rows, and Columns.
Before you normalize your data objects, check that they fit these rules. To normalize your data objects, analyze the dependencies between the entities, relationships, and attributes. Normalization is discussed in Normalizing a Data Model.
After you normalize the data model, you can use SQL statements to create a database that is based on your data model. Implementing a Relational Data Model describes how to create a database and provides the database schema for the telephone directory example.
Each entity that you choose is represented as a table in the model. The table stands for the entity as an abstract concept, and each row represents a specific, individual occurrence of the entity. In addition, each attribute of an entity is represented by a column in the table.
The following ideas are fundamental to most relational data-model methods, including the E-R data model. Follow these rules while you design your data model to save time and effort when you normalize your model.
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