case statement in select query in sql server

A special scalar expression in SQL language is CASE expression. SQL CASE expression is used as a kind of IF-THEN-ELSE statement. It is similar to switch statement in modern programming language such as Java or C#. The syntax of the CASE statement is simple as follows :






SELECT name,salary,  
CASE      
WHEN  salary <= 2000 THEN 'low'
WHEN  salary > 2000 AND salary <= 3000 THEN 'average'
WHEN  salary > 3000 THEN 'high'
END AS salary_level  
FROM employees  
ORDER BY salary ASC