why "/" and "-"  in the line?

remove   -s""   (default spacing) .

DECLARE  @user1 varchar(50)

SELECT @user1 = 'New_Column_Name'

declare @sentencia_sql nvarchar(1000)

declare @Sal int

select @sentencia_sql='SelECT User1 AS ' + @user1 + '

from _user'

EXECUTE @Sal=sp_executesql...

Good  thank  , bien gracias , tratare de buscar bien el for