how to alias a table

I'm refactoring some code and I'll find helpful to be able to alias
tables.

What I'd like to do would be to refer to the same table with an
alias in the code and later substitute the alias with an actual VIEW.

Of course I could define a view as
select * from original_table
right from the start but I'm worried this may incur in some overhead
I currently can't afford.

thanks

--
Ivan Sergio Borgonovo
http://www.webthatworks.it