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Why is aliasing necessary in a self join query?

hard📝 Conceptual Q10 of 15
SQL - INNER JOIN
Why is aliasing necessary in a self join query?
ATo speed up query execution
BTo distinguish between two instances of the same table
CTo avoid using JOIN keyword
DTo create temporary tables
Step-by-Step Solution
Solution:

  1. Step 1: Understand self join structure

    Self join uses the same table twice in one query.

  2. Step 2: Role of aliasing

    Aliasing gives each instance a unique name to refer to columns clearly and avoid confusion.

  3. Final Answer:

    To distinguish between two instances of the same table -> Option B

  4. Quick Check:

    Aliasing differentiates table instances [OK]
Quick Trick: Alias tables to avoid confusion in self join [OK]
Common Mistakes:
MISTAKES
  • Thinking alias speeds query
  • Confusing alias with temp tables
  • Ignoring alias causes errors

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