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Why do we use aggregation functions like SUM() or COUNT() in SQL?

easy📝 Conceptual Q11 of 15
SQL - Aggregate Functions
Why do we use aggregation functions like SUM() or COUNT() in SQL?
ATo summarize multiple rows into a single value
BTo delete rows from a table
CTo change the data type of a column
DTo create a new table
Step-by-Step Solution
Solution:

  1. Step 1: Understand aggregation functions

    Aggregation functions like SUM and COUNT combine many rows into one summary value.

  2. Step 2: Identify the purpose of aggregation

    They help get totals, counts, or averages instead of listing every row.

  3. Final Answer:

    To summarize multiple rows into a single value -> Option A

  4. Quick Check:

    Aggregation = summarize rows [OK]
Quick Trick: Aggregation combines rows into one summary value [OK]
Common Mistakes:
MISTAKES
  • Thinking aggregation deletes data
  • Confusing aggregation with data type changes
  • Assuming aggregation creates new tables

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