The classes of relations produced by normalization to avoid modification anomalies are called what?
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Anormal forms.
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Breferential integrity constraints.
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Cfunctional dependencies.
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DNone of the above is correct.
Answer
Correct Answer: normal forms.
Explanation
Introduction / Context:Normalization organizes relational schemas to reduce redundancy and eliminate update, insert, and delete anomalies. The outcomes are categorized into named stages.
Given Data / Assumptions:
- Well-known levels include first, second, and third normal form, plus Boyce–Codd and beyond.
- Anomalies arise when one table tries to represent multiple themes or has improper dependencies.
Concept / Approach:Each stage of normalization corresponds to a normal form. These forms impose increasingly strict rules based on functional and other dependencies to mitigate anomalies.
Step-by-Step Solution:
Identify the artifact that names the stages: they are the normal forms.Eliminate options that are inputs or constraints rather than the classification.Select normal forms as the correct label.Verification / Alternative check:Textbook definitions explicitly refer to 1NF, 2NF, 3NF, BCNF, 4NF, and 5NF as normal forms addressing anomalies.
Why Other Options Are Wrong:
- Referential integrity constraints enforce key–foreign key consistency, not the classification of normalized schemas.
- Functional dependencies are relationships used to reason about normalization, not the stages themselves.
Common Pitfalls:Confusing the tools (dependencies, constraints) with the results (normal forms).
Final Answer:normal forms.