Conceptual modeling looks at how the data is structured and what the characteristics of the data are. What characteristics of data are represented in an E-R diagram?
o Characteristics for attributes are also called properties. So every entity must have attributes to help make it unique. Behavior is important because the entity responds to other entities. For example, a person entity inserts a credit card into an ATM entity; the ATM entity responds with an action.The person will react differently depending on what the ATM does (reject or accept the credit card). What are at least three other examples of behaviors for other entities? (Please create your own examples,and do not copy from the Internet.)
o Cardinality describes the actual number of entities of the same type involved in a process. So in our class we have 30 students of the student entity type. The cardinality would then be described as 30 students. We can describe the number as 0, 1, many (and then can display the actual minimum and maximum allowed). We can also say whether the number is optional or mandatory. For instance, it is mandatory we have one instructor for our class. It is not optional. What are at least three other examples of cardinality?
Use APA format.
• You are expected to cite at least two academic references.
• The essay should be about two pages in length, double spaced, with standard margins.
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