concatenate two database columns into one resultset column

Question

I use the following SQL to concatenate several database columns from one table into one column in the result set:

SELECT (field1 + \'\' + field2 + \'\' + field

Answer 1

Just Cast Column As Varchar(Size)

If both Column are numeric then use code below.

Example:

Select (Cast(Col1 as Varchar(20)) + '-' + Cast(Col2 as Varchar(20))) As Col3 from Table

What will be the size of col3 it will be 40 or something else