SQL Server OR Operator

Summary: in this tutorial, you will learn how to use the SQL Server OR operator to combine two Boolean expressions.

Introduction to SQL Server OR operator

The SQL Server OR is a logical operator that allows you to combine two Boolean expressions. It returns TRUE when either of the conditions evaluates to TRUE.

The following shows the syntax of the OR operator:

boolean_expression OR boolean_expressionCode language: SQL (Structured Query Language) (sql)

In this syntax, the boolean_expression is any valid Boolean expression that evaluates to true, false, and unknown.

The following table shows the results of the OR operator when you combine TRUE, FALSE, and UNKNOWN:

When you use multiple logical operators in an expression, SQL Server always evaluates the OR operators after AND operators. But you can use the parentheses () to change the order of the evaluation.

SQL Server OR operator examples

We’ll use the following production.roducts table from the sample database.

1) Basic SQL Server OR operator example

The following example uses the OR operator to find the products whose list price is less than 200 or greater than 6,000:

SELECT
    product_name,
    list_price
FROM
    production.products
WHERE
    list_price < 200
OR list_price > 6000
ORDER BY
    list_price;
Code language: SQL (Structured Query Language) (sql)

2) Using multiple OR operators

The following statement uses multiple OR operators to find the products whose brand id is 1, 2, or 4:

SELECT
    product_name,
    brand_id
FROM
    production.products
WHERE
    brand_id = 1
OR brand_id = 2
OR brand_id = 4
ORDER BY
    brand_id DESC;
Code language: SQL (Structured Query Language) (sql)

You can replace multiple OR operators by the IN operator as shown in the following query:

SELECT
    product_name,
    brand_id
FROM
    production.products
WHERE
    brand_id IN (1, 2, 3)
ORDER BY
    brand_id DESC;
Code language: SQL (Structured Query Language) (sql)

3) Combining the OR operator with the AND operator

The following example shows how to combine the OR operator with the AND operator within the same expression:

SELECT 
    product_name, 
    brand_id, 
    list_price
FROM 
    production.products
WHERE 
    brand_id = 1
      OR brand_id = 2
      AND list_price > 500
ORDER BY 
    brand_id DESC, 
    list_price;Code language: SQL (Structured Query Language) (sql)

In this example, we used both OR and AND operators. As always, SQL Server evaluated the AND operator first. Therefore, the query returned the products whose brand id is 2 and the list price is greater than 500 or those whose brand id is 1.

To find the products whose brand id is 1 or 2 and list price is greater than 500, you use the parentheses as shown in the following query:

SELECT
    product_name,
    brand_id,
    list_price
FROM
    production.products
WHERE
    (brand_id = 1 OR brand_id = 2)
     AND list_price > 500
ORDER BY
    brand_id;Code language: SQL (Structured Query Language) (sql)

Summary

• Use the SQL Server OR operator to combine two Boolean expressions.
• The OR operator returns TRUE if one of the expressions is TRUE.
• By default, SQL Server evaluates the OR operators after the AND operators within the same expression. But you can use parentheses () to change the order of evaluation.