Combines two conditions. When more than one logical operator is used in a statement, OR operators are evaluated after AND operators. However, you can change the order of evaluation by using parentheses.
-- Syntax for SQL Server, Azure SQL Database, Azure SQL Data Warehouse, Parallel Data Warehouse boolean_expression OR boolean_expression
Is any valid expression that returns TRUE, FALSE, or UNKNOWN.
OR returns TRUE when either of the conditions is TRUE.
The following table shows the result of the OR operator.
The following example uses the
vEmployeeDepartmentHistory view to retrieve the names of
Quality Assurance personnel who work either the evening shift or the night shift. If the parentheses are omitted, the query returns
Quality Assurance employees who work the evening shift and all employees who work the night shift.
-- Uses AdventureWorks SELECT FirstName, LastName, Shift FROM HumanResources.vEmployeeDepartmentHistory WHERE Department = 'Quality Assurance' AND (Shift = 'Evening' OR Shift = 'Night');
Here is the result set.
FirstName LastName Shift
------------ ---------------- -------
Andreas Berglund Evening
Sootha Charncherngkha Night
The following example retrieves the names of employees who either earn a
BaseRate less than 20 or have a
HireDate January 1, 2001 or later.
-- Uses AdventureWorks SELECT FirstName, LastName, BaseRate, HireDate FROM DimEmployee WHERE BaseRate < 10 OR HireDate >= '2001-01-01';