There is only 20 "3" after ".". Well, may be this is not a problem, but
why are they infinite number of "0" after the point? I can write even
=> select (1::numeric/3-0.33333333333333333333)* 1e100000;
?column?
------------------------
0.00000000000000000000
Result the same. According to the docs: "Numeric values are physically
stored without any extra leading or trailing zeroes."
What you see on the screen is not what is physically stored. The documentation about the numeric type on the server is accurate, but apparently the psql application takes some liberties as to what it chooses to display. It's display rules for numeric don't seem to be user documented or configurable.
David J,