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Why is Third Normal Form (3NF) important in database design?

easy📝 Conceptual Q2 of 15
SQL - Database Design and Normalization
Why is Third Normal Form (3NF) important in database design?
ATo eliminate redundant data and avoid update anomalies
BTo speed up query execution by denormalizing tables
CTo allow multiple primary keys in a table
DTo store data in a single table only
Step-by-Step Solution
Solution:

  1. Step 1: Identify the goal of 3NF

    3NF aims to reduce redundancy and prevent update, insert, and delete anomalies.

  2. Step 2: Understand effects of normalization

    By removing transitive dependencies, data is stored efficiently and consistently.

  3. Final Answer:

    To eliminate redundant data and avoid update anomalies -> Option A

  4. Quick Check:

    3NF purpose = Remove redundancy [OK]
Quick Trick: 3NF helps keep data consistent and non-redundant [OK]
Common Mistakes:
  • Thinking 3NF is for faster queries
  • Believing 3NF allows multiple primary keys
  • Assuming 3NF means one big table

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