into columns - Decide what information needs to be stored in each table. Each item becomes a field, and is displayed as a column in the table. For example, an Employees table might include fields such as Last Name and Hire Date. Specify primary keys - Choose each table's primary key. The primary key is a column, or a set of columns, that is used to uniquely identify each row. An example might be Product ID or Order ID. Set up the table relationships - Look at each table and decide how the data in one table is related to the data in other tables. Add fields to tables or create new tables to clarify the relationships, as necessary. Refine the design - Analyze the design for errors. Create tables and add a few records of sample data. Check if results come from the tables as expected. Make adjustments to the design, as needed. Apply the normalization rules - Apply the data normalization rules to see if tables are structured correctly. Make adjustments to the tables, as needed. Normalization In the field of relational database design, normalization is a systematic way of ensuring that a database structure is suitable for general-purpose querying and free of certain undesirable characteristics—insertion, update, and deletion anomalies that could lead to loss of data integrity. A standard piece of database design guidance is that the designer should create a fully normalized design; selective denormalization can subsequently be performed, but only for performance reasons. The trade-off is storage space vs performance. The more normalized the design is, the less data redundancy there is (and therefore, it takes up less space to store), however, common data retrieval patterns may now need complex joins, merges, and sorts to occur - which takes up more data read, and compute cycles. Some modeling disciplines, such as the dimensional modeling approach to data warehouse design, explicitly recommend non-normalized designs, i.e. designs that in large part do not adhere to 3NF. Normalization consists of normal forms that are 1NF,2NF,3NF,BOYCE-CODD NF (3.5NF),4NF and 5NF Document databases take a different approach. A document that is stored in such a database, typically would contain more than one normalized data unit and often the relationships between the units as well. If all the data units and the relationships in question are often retrieved together, then this approach optimizes the number of retrieves. It also simplifies how