How do Entity relationship Diagrams (ERDs) help to ensure proper informationbase blood line?The importance of proper informationbase design was hatched in DQ1 of this week. Entity birth Diagrams (ERDs) help ensure proper database design by graphically showing the structure of a database. ERDs also help us learn key concepts about the data we need to practice or manipulate. For example, ERDs indicate:1. data relationships such as One-to-Many, Many-to-Many, Ambiguities2. what data needs to be stored3. the degree of a relationshipThe ERDs helps us evaluate the design and to envision aras that whitethorn be of concern, or areas we may have missed. In an online lecture, Data Modeling with Entity Relationship Diagrams by Frances Wickham from the Medical University of South Carolina (http://www.srnr.arizona.edu/rnr/rnr417/erdiagrams3/erdiagrams.htm)Wickham indicates that data models such as ERDs are used as communication tools and also, ?provide the deve loper an opportunity to general anatomy out conceptual and design issues and problems prior to beginning the in truth design process.?Wickham compares building a database to micturateing a building, the ERD is the blueprint from which the database set out be built, and ?no reputable builder would start to compose a building without a detailed blueprint.?An entity is a person, nail down or thing about which data can be stored for tracking by the user.

For example, an entity can be a customer, and the data that will be stored for that entity can be: the customer?s account number, the customer?s name, the custo mer?s extension and the customer?s phone num! ber. Relationship is the interaction encircled by entities. For example, a customer which is an entity places an order at the community?s web-store which is also another entity. Placing the order is the link amidst the both entities, thus the relationshipOnce the database tables have been created for the database it is then important to understand how the entities... If you exigency to get a full essay, order it on our website:
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