The school recently held a **competition** for students who participated in **Mathematics**. Some students were rewarded, but now the school wants to ensure no students **cheated** by taking **more than one** exam, including the math exam.

Your task is to **find the last names** of students who took **more than one** exam, with one of them being `Mathematics`.

Here is the query from our **previous assignment** that you can use as an example:



SELECT student_surname, AVG(grade) as average_grade
FROM student_grades
GROUP BY student_surname
HAVING COUNT(grade) > 1

This course is perfect for those who already have a basic understanding of SQL and want to delve into more advanced concepts to craft more powerful queries. Throughout the course, you will become familiar with data grouping and filtering grouped data. You will also learn how to work with multiple tables simultaneously, including how to combine them. Additionally, you will explore different types of table joins and how to apply them in practice.

In this section, you will learn how to group and manage data effectively. We will introduce the GROUP BY operator for grouping data. Additionally, you will learn how to filter grouped data using the HAVING operator.

You will learn about nested subqueries, how to create them, and how to use them effectively.

Here, you will learn how to combine multiple tables, allowing you to work with a unified table and simplify query creation.

Learn the fundamentals of Data Definition Language (DDL) and Data Manipulation Language (DML) in SQL, including how to create, modify, and delete database objects, as well as how to insert, update, and delete data within tables.

More Complex Filtering

Brief Instructions

Solution

More Complex Filtering

Brief Instructions

Solution