Summary  
This chapter covers using the DISTINCT keyword in a SELECT statement to retrieve unique values from a column.  

General domain of usage  
Relational database querying

Note that the `SELECT` statement returns all rows in a given column. However, what if we don't need all the values from a column, especially when they are duplicated, and we only need **unique values**? 

For such cases, it is convenient to use the keyword `DISTINCT`, placed immediately before the column names. Let's take a look at an example:

What does the `DISTINCT` keyword do in a `SELECT` statement?

Which SQL clause is used to remove duplicate rows from the result set?

This course is perfect for beginners ready to explore the world of SQL. Whether you're just starting out in database management or aiming to use SQL for your application development projects, this course covers the essentials. You'll quickly learn how to leverage the full potential of SQL, from querying and managing data to seamlessly integrating it into real-world applications. By the end of the course, you'll have the confidence and skills to solve practical problems with SQL and enhance your development process.

In this section, we will learn how to use the SQL SELECT statement to get a single table column, multiple table columns, and all table columns. We will also find out how to return unique values.

In this section, we’ll explore how to organize and prioritize the data returned by a query using the ORDER BY clause. Placed at the end of a SELECT statement, this clause lets you sort your results by one or multiple columns, either in ascending or descending order, enabling more meaningful and easily interpretable data output.

In this section, we will learn how to filter returned data using the SELECT statement's WHERE clause. We will learn how to test for equality, inequality, more and less significant than value ranges, and NULL values.

In this section, we’ll explore how to refine your search conditions by combining WHERE clauses with the AND and OR operators. We’ll also cover how the NOT operator can be used to exclude certain results.

In this section, we will learn what the SQL aggregate functions are and how to use them to summarize table data.

Retrieving Distinct Rows

1. What does the `DISTINCT` keyword do in a `SELECT` statement?

2. Which SQL clause is used to remove duplicate rows from the result set?

Retrieving Distinct Rows

1. What does the DISTINCT keyword do in a SELECT statement?

2. Which SQL clause is used to remove duplicate rows from the result set?

1. What does the `DISTINCT` keyword do in a `SELECT` statement?