E/R MODELLING Terminology, Keys and Weak Entities

Can you name & explain each name part of a table?
Domains
Attributes
Attribute Values
Tuple
Degree
Cardinality
- Domains can restrict the allowed attribute values
What is functional dependencies?
What is a valid function dependency and what is not?
Functional dependency, If two rows(r1),(r4) in a column(SSN) has the same attribute(111) then they must also have the same tributes(SMITH) in the other column(LAST) to be funtionaly dependent.Does the X determine they y? if x and y is known can u go to ever x and get the same y? if not then not dependent.
What are keys in the ER model?
Example?
many?
When and why does week entity exist?
Why is a relationship involved?
Give example of a week relationship with two entitis and total of 3 attributes.
ER diagrams vs. EER diagrams whats the differance and what do they contain?

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E/R MODELLING Terminology, Keys and Weak Entities

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E/R MODELLING Keys and Weak Entities

Updated

2020-06-05T11:48:07Z

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