In a database, relationships between data are represented in tables by records (rows) and fields (columns).
Each table is devoted to a specific subject, such as employee addresses, customer orders, shipping methods, or suppliers. Each person or thing that belongs in a table's subject, and the data about that person or thing, forms a record. For example, details about Shipper ID 2, United Package, form a record.
Each specific type of information about a person or thing, such as last name, address, or phone, is a field. For example, Phone is a field in the Shippers table.
Each field and record should be unique. For example, the data for Speedy Express should not be repeated in another record; "Company Name" should appear only once as a field name.
Entries in a single table should all be of the same kind. The Shippers table should contain only names of shippers and data about shippers. No data except phone numbers should be placed in the Phone field.
Before you create your database, you should analyze your data and determine how it can be divided into well-structured separate tables.
