SQL NVL

The SQL NVL function is used to replace NULL value with an alternate value in Oracle. It’s similar to MS SQL Server’s ISNULL Function and mySQL’s IFNULL Function.

SQL NVL Function Syntax

NVL(exp1, exp2)

If exp1 is null, the NVL function will return exp2, otherwise it will return exp1. Exp1 and exp2 should be same or compatible with the data type.

SQL NVL Function Example

Table: Employees

Example 1

SELECT EmployeeId, NVL(Salary, 50000) AS Salary 
FROM Employees;

The result will look like:

Example 2

SELECT SUM(NVL(Salary, 50000)) AS TotalSalary 
FROM Employees;

The result will look like: