Re: Do we need multiple forms of the SQL2003 statistics

Peter Eisentraut <peter_e@gmx.net> writes:
> ... From a mathematician's point of view, however, some of these 
> functions normally produce irrational numbers anyway, so it seems 
> unlikely that numeric will be useful.  But looking at the definition 
> of, say, regr_avgx(Y, X), if all the input values are integers, it 
> might be useful if I could get an exact integer or rational number as 
> output, instead of a float, that is.

The question is whether this is useful enough to justify adding a
thousand lines to numeric.c.

I believe also that the numeric forms of the aggregates will be
enormously slower than the float forms, at least on most modern
machines with decent floating-point performance.  I don't have time
to do any performance testing though.
        regards, tom lane