SQL Sorting and Limiting Results 4

Question 1

Can you use a column alias defined in SELECT inside ORDER BY?

Accepted Answer

Yes, in most databases

Answer

ORDER BY runs after SELECT, so column aliases are usable there.

Question 2

Which query finds the top 3 highest-priced products?

Accepted Answer

ORDER BY price DESC LIMIT 3

Answer

Sorting price descending and limiting to 3 returns the most expensive items.

Question 3

What is the risk of using LIMIT/OFFSET for pagination on large tables?

Accepted Answer

Large offsets get slower as they scan and skip rows

Answer

High OFFSET values force the database to scan and discard many rows, hurting performance.

Question 4

Which expression sorts case-insensitively in many databases?

Accepted Answer

ORDER BY LOWER(name)

Answer

Applying LOWER() to the column normalizes case before sorting.

Question 5

Can ORDER BY use an expression like ORDER BY price * quantity?

Accepted Answer

Yes, expressions are allowed

Answer

ORDER BY accepts arbitrary expressions, not just plain columns.

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