A major use case missed is use of the OVER clause:

select

id,

name,

designation,

Salary,

AVG(salary) over (partition by designation) Avg_Sal

from [dbo].[Associates]

would yield the entire list, along with the average salary for all with the...

What is more interesting is that

IF (1 <> 1)

BEGIN

DECLARE @NumOfHolidays INT;

SET @NumOfHolidays = 0;

END

SELECT @NumOfHolidays;

returns null, not an error