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6. EMPLOYEE manipulates with CUSTOMER.
Assignment 4: Database Modeling and Normalization 4After determining the relationships, it must draw them with all the lines between the entities andthe relationships, by the ERM: (Relationship by the Diamond figure).Fig (2): Entities with the relationships3.Determine the relationship type (1:1), (1: M), or (M: N). Every relationship type has a specificsymbol to implement it.
Assignment 4: Database Modeling and Normalization 5Fig (3): Symbols and their meaningsFor ExampleOne manager manages many employees: (1: M): We can implement thisrelationship as the following: One and only one manager can manage one or many employees. Fig(4): Entities with relationships types4. In the end, we must identify the entity attributes and then check the result.(infocom.cqu.edu.au, 2006). The end figure as the following:
Assignment 4: Database Modeling and Normalization 6Fig (5): The End Figure (Entities, relationships types, and the attributes)The risks that can occur if any of the developmental or iterative steps of creating an ERMDiagram are not performed:Any organization has the following components: Entities, Attributes, Relationships, andConstraints. The Org. Entities are the main things by it the database model is built. The attributesare the features of the Entities, and the relationships are the describing of the set of correlation
Assignment 4: Database Modeling and Normalization 7among the entities. While the constraint is the limitation of the relationship, and it is veryimportant to ensure the database integrity. (Carlos Coronel, et al., 2013).There is no standard modeling that is suitable for all the system types, but every modelmust align the organization requirements. Every organization has its specific components;therefore, it must have the specific model for its system. These system components are thecollection of to implement the system model; therefore, all of it must be founded. If any one ofthe system components is missed, then the modeling design didn't implement the systemrequirements, many risks must be faced. Also, the database model may fail. (McDonald,Caroline, 2004).Entities that would be required for the development of the data repositories:There are various effective entities in the government companies that is required for thedevelopment of the data repositories. The entities are implemented by the departments in thecompanies, the tasks that are performed in this company, and other. The very important entitiesare the management, department (such as planning, training, security, hiring, etc.), employee,salary, and the customer entity. (Caroline Gilbert, 2011).