What are the different ways to replace NULL values in SQL Server

What are the different ways to replace NULL values in SQL Server

 we can use COALESCE() to replace NULL values SQL Server.  That's very good answer, but do you know of any other way?


Apart from using COALESCE(), there are 2 other ways to replace NULL values in SQL Server. Let's understand this with an example.


I have a Table tblEmployee, as shown in the diagram below. Some of the Employees does not have gender. All those employees who does not have Gender, must have a replacement value of 'No Gender' in your query result. Let's explore all the 3 possible options we have.


Option 1 : Replace NULL values in SQL Server using ISNULL() function.

Select Name, ISNULL(Gender,'No Gender') as Gender
From tblEmployee



Option 2 : Replace NULL values in SQL Server using CASE.

Select Name, Case When Gender IS NULL Then 'No Gender' Else Gender End as Gender
From tblEmployee



Option 3 : Replace NULL values in SQL Server using COALESCE() function.

Select Name, Coalesce(Gender, 'No Gender') as Gender
From tblEmployee