Example
The Cast() function is used to convert a data type variable or data from one data type to another data type.
Syntax
CAST ( [Expression] AS Datatype)
The data type to which you are casting an expression is the target type. The data type of the expression from which you are casting is the source type.
DECLARE @A varchar(2)
DECLARE @B varchar(2)
set @A='25a'
set @B='15'
Select CAST(@A as int) + CAST(@B as int) as Result
--'25a' is casted to 25 (string to int)
--'15' is casted to 15 (string to int)
--Result
--40
DECLARE @C varchar(2) = 'a'
select CAST(@C as int) as Result
--Result
--Conversion failed when converting the varchar value 'a' to data type int.
Throws error if failed
