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Designing databasesThe first step in creating a relational database is to construct a data model, which is a precise, complete definition of the data you want to store. After you prepare your data model, you must implement it as a database and tables. To implement your data model, you first select a data type for each column and then you create a database and tables and populate the tables with data. You can also implement fragmentation strategies and control access to your data.
Designing and Implementing a DatabaseThese topics provide information to help you design, implement, and manage your HCL® OneDB® databases. It includes data models that illustrate different approaches to database design and shows you how to use structured query language (SQL) to implement and manage your databases.The HCL OneDB™ Database Design and Implementation Guide provides information to help you design, implement, and manage your HCL® OneDB® databases. It includes data models that illustrate different approaches to database design and shows you how to use structured query language (SQL) to implement and manage your databases.
Basics of database design and implementation
Build a relational data model
Identify and define principal data objects
Discover entities
Telephone directory example

Telephone directory example

Suppose that you create a database for a personal telephone directory. The database model must record the names, addresses, and telephone numbers of people and organizations that the user requires.

First define the entities. Look carefully at a page from a telephone directory to identify the entities that it contains. The following figure shows a sample page from a telephone directory.

The graphic shows three entries in an address book. Each entry has labeled places for Name, Phone, and Address. For example, Entry 1 shows: Name: Catherine Morgan Phone: 206-789-5396 First line of the Address: 429 Bridge Way Second line of the Address: Seattle, WA 98103. — Figure 1: Partial page from a telephone directory

The physical form of the existing data can be misleading. Do not let the layout of pages and entries in the telephone directory mislead you into trying to specify an entity that represents one entry in the book: an alphabetized record with fields for name, number, and address. You want to model the data, not the medium.