<p>Is there a way to make a TSQL variable constant?</p>

There are no such thing as "creating a constant" in database literature. Constants exist as they are and often called values. One can declare a variable and assign a value (constant) to it. From a scholastic view:
```
```
DECLARE @two INT
SET @two = 2
```
```
Here @two is a variable and 2 is a value/constant.