Is it possible to eliminate PROJECTION operator when optimizing an SQL query?

Question

For an SQL query:

select * from t where R

we'll first optimize the ast built from this SQL, and get a logical plan, like Projection -- > Selection -- > t

Is it possible to eliminate the PROJECTION part?

Answer 1

As you can see from the What are projection and selection? SO topic, projection

means choosing which columns (or expressions) the query shall return

Therefore, this step can hardly be skipped.