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:
In this syntax, the
boolean_expression
is any valid Boolean expression that evaluates to true, false, and unknown.
The following table shows the result of the
OR
operator when you combine TRUE
, FALSE
, and UNKNOWN
:TRUE | FALSE | UNKNOWN | |
---|---|---|---|
TRUE | TRUE | TRUE | TRUE |
FALSE | TRUE | FALSE | UNKNOWN |
UNKNOWN | TRUE | UNKNOWN | UNKNOWN |
When you use more than one logical operator in a statement, SQL Server evaluates the
OR
operators after the AND
operator. However, you can use the parentheses to change the order of evaluation.
SQL Server OR
operator examples
See the following
production.roducts
table from the sample database.
A) Using OR
operator example
The following example finds the products whose list price is less than 200 or greater than 6,000:

B) Using multiple OR
operators example
The following statement finds the products whose brand id is 1, 2, or 4:

You can replace multiple
OR
operators by the IN
operator as shown in the following query:
C) Using OR
operator with AND
operator example
Consider the following example:

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 the products 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:

In this tutorial, you have learned how to use the SQL Server
OR
operator to form a condition by combining two Boolean expressions.
0 Comments