Avoiding Unnecessary DATA Steps

Suppose BigOne is stored in a subdirectory referred to by the reference name Library. Consider the code:

data CopyOfIt;
	set Library.BigOne;

Proc Means data=CopyOfIt;
	Var X1 X2;
run;

Is the data step that creates CopyOfIt necessary? Instead, use this code:

Proc Means data=Library.BigOne;
	Var X1 X2;
run;