Summary  
This chapter demonstrates how to apply the OR logical operator to combine multiple conditional filters in a SQL query.

General domain of usage  
Relational database querying

The `OR` operator is used to filter records based on more than one condition, like if you want to return all countries from Asia but also those from Europe.

Here is the syntax of using the OR operator:

```sql
SELECT columns
FROM table
WHERE column = 'first_option' OR column = 'second_option';
```

Let's look at the example:

SELECT name, population, continent, region
FROM country
WHERE continent = 'Asia' OR continent = 'Europe';

Which SQL query correctly uses the OR operator to select countries from either Asia or Europe

Which query will return countries with population greater than 50 million or surface area less than 100000

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.

Using the OR operator

1. Which SQL query correctly uses the OR operator to select countries from either Asia or Europe

2. Which query will return countries with population greater than 50 million or surface area less than 100000