Normalize the Entities

Data Modeling › Data Model › Normalize the Entities

Normalize the Entities

Normalization of data is a procedure that ensures that a data model conforms to some useful standards.

For data and entity relationship models, the following standards have been defined to minimize duplication of data, to provide the flexibility necessary to support different functional requirements, and to enable the data model to be mapped onto a relational database design effectively.

Eliminate repeating data groups
Eliminate partial key dependencies
Eliminate non-key dependencies (attributes that depend upon another non-key attribute in the entity)

Although the steps are listed and briefly discussed here, you may wish to consult additional sources for a more detailed description.

Applying these steps causes the entities and attributes to be redefined as follows:

Entity	Attribute	Primary Key	Foreign Key
COURSE	Course code Course name	Course code	N/A
HORSE	Horse code Horse name Horse gender Date of birth	Horse code	N/A
JOCKEY	Jockey code Jockey name Jockey gender	Jockey code	N/A
SIRE	Sire code Sire name Sire Date of birth	Sire code	N/A
DAM	Dam code Dam name Dam Date of birth	Dam code	N/A
RACE	Course code Race date Race time Race name Going conditions Distance Prize money	Course code Race date Race time	N/A
RACE ENTRY	Course code Race date Race time Entry number Horse code Jockey code Finishing position Handicap Entry status	Course code Race date Entry number	Horse code Jockey code

This process has resulted in the creation of another entity named RACE ENTRY. Now our Entity Relationship Diagram looks like this. Note that K indicates a key attribute and A indicates a foreign key (non-key attribute).