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Question
A relation is in third normal form (3NF) if and only if it is in 2NF and ________.A) all non-key attributes are determined by the entire primary key
B) there are no non-key attributes determined by another non-key attribute
C) every attribute is a candidate key
D) every candidate key is a determinant
Answer
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Related questions
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Suppose you have created a data model for an airline based on a variety of forms, reports, user interviews, data sources, etc. Your client comes forward with a new desired report that includes passenger weights and a relationship between passengers and employees, neither of which is in your E-R diagram. You should ________.
A) create a new, separate E-R diagram with just the new information
B) add the relationship and the weight attribute to the existing data model
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ID-dependent entities are a common type of weak entity.
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Q:
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B) limits the number of rows retrieved from a table
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