efficient (in size) integer datatype?

What would be the most efficient (in terms of minimizing storage space) of using INTEGER, SMALL_INT, NUMBER(3), BINARY_INTEGER, or NATURAL for a variable which can have values in the 0 to 255 range?

I would have thought SMALL_INT, but a table in the Oracle PL/SQL Programming book by Steven Feuerstein/O'Reilly says that SMALL_INT is stored internally as NUMBER(38) (same as INT or INTEGER), which makes me wonder if the # of bytes to store a SMALL_INT is actually quite large (to handle the max. of 38 digits of precision).

Thanks for any insights!

Paul

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• Paul J. Wagner School - wagner_at_cs.umn.edu *
• Computer Science Department Work - wagnerp_at_uwstout.edu *
• University of Minnesota *
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