Quiz on Aggregate Functions in SQL

In a school database, Emma wants to know the average score of all students in the math exam. What do aggregate functions in SQL primarily do to help her?

• Filter data based on specific conditions

• Join multiple tables together

• Perform calculations on multiple rows and return a single value

• Sort data in ascending order

In a school, Abigail is calculating the total score of her classmates in a math competition. Which of the following functions would she use to find the total score?

• JOIN()

• WHERE()

• SELECT()

• SUM()

Henry wants to find out how well he performed in his math class. He decides to use the AVG() function to calculate his grades. What does the AVG() function calculate?

• The total of all values

• The average of a set of values

• The highest value in a column

• The lowest value in a column

In a classroom, Arjun wants to know how many students attended the lecture. What is the purpose of the COUNT() function?

• To find the maximum value in a column

• To count the number of rows in a dataset

• To calculate the average of a dataset

• To sum all numeric values

In a school, a teacher wants to analyze the test scores of students. Which SQL clause should the teacher use to group the scores of students with the same values?

• ORDER BY

• HAVING

• GROUP BY

• SELECT

In a school, Rohan wants to find out how many students scored above average in their exams. He uses the HAVING clause to filter the results after calculating the average scores of all students.

• Groups data into categories

• Sorts data in descending order

• Filters results after aggregation

• Filters results before aggregation

Sophia is working on a project where she needs to create a new table in her database to store customer information. What is the function of the SELECT INTO command?

• To create a new table and insert data into it

• To update existing records in a table

• To retrieve data from multiple tables

• To delete records from a table

In a company where Scarlett works, which SQL query would find the highest salary among the employees?

• SELECT MAX(salary) FROM employees

• SELECT AVG(salary) FROM employees

• SELECT MIN(salary) FROM employees

• SELECT SUM(salary) FROM employees

In a school, Zoe wants to analyze the students' grades by subject. What is the purpose of using GROUP BY in SQL for her analysis?

• To create new tables from existing data

• To filter data based on conditions

• To sort data in a specific order

• To categorize data into meaningful summaries

Which SQL query would find the average GPA of students in each department at the university where William, Isla, and Hannah are enrolled?

• SELECT department, MAX(gpa) FROM students GROUP BY department

• SELECT department, COUNT(gpa) FROM students GROUP BY department

• SELECT department, AVG(gpa) FROM students GROUP BY department

• SELECT department, SUM(gpa) FROM students GROUP BY department