CASE WHEN

Question 1

What is the primary purpose of using **CASE WHEN** in the SELECT clause?

A.

A) To filter rows before grouping

B.

B) To create computed columns for data categorization

Explanation: **CASE WHEN** generates new columns by evaluating conditions and assigning labels, such as categorizing data based on values.

C.

C) To join multiple tables

D.

D) To calculate aggregate sums

Question 2

What is the primary purpose of using **CASE WHEN** in the **ORDER BY** clause?

A.

A) To define custom priority sorting for values

**Explanation:** **CASE WHEN** in **ORDER BY** creates conditional sorting priorities, with lower assigned numbers appearing first.

B.

B) To filter rows based on conditions

C.

C) To calculate new columns in the SELECT list

D.

D) To join multiple tables

Question 3

What is the primary purpose of using **CASE WHEN** in the WHERE clause?

A.

A) To sort query results

B.

B) To aggregate column values

C.

C) To join multiple tables

D.

D) To handle complex conditional logic for row filtering

Explanation: **CASE WHEN** extends the WHERE clause to evaluate multiple conditions and return a value for filtering, improving organization over simple comparisons

Question 4

What is the primary benefit of using **CASE WHEN** in the **HAVING** clause over simple aggregate conditions?

A.

A. It allows filtering before grouping data

B.

B. It applies different threshold criteria to different groups based on column values

Explanation: **CASE WHEN** in **HAVING** enables category-specific filtering logic, evaluating groups against varying thresholds rather than uniform conditions.

C.

C. It eliminates the need for a GROUP BY clause

D.

D. It converts aggregate functions to scalar values

📝 CASE WHEN

Quiz Complete!