Re: dividing money by money

Peter Eisentraut <peter_e@gmx.net>

From: Peter Eisentraut <peter_e@gmx.net>
To: Kevin Grittner <Kevin.Grittner@wicourts.gov>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Andy Balholm <andy@balholm.com>, pgsql-hackers@postgresql.org
Date: 2010-07-17T10:20:23Z
Lists: pgsql-hackers
On fre, 2010-07-16 at 08:55 -0500, Kevin Grittner wrote:
> Peter Eisentraut <peter_e@gmx.net> wrote:
>  
> > I didn't see any discussion about why this should return float8
> > rather than numeric.  It seems wrong to use float8 for this.
>  
> That discussion took place several months ago on the -bugs list. 
> I'll paste some links from a quick search of the archives below. 
> Since multiplication of money is by float8 and not numeric, it
> ultimately seemed more consistent to me to have the results of
> division be float8.  I felt that as long as we had a cast between
> money and numeric, someone could always cast to numeric if they
> wanted that style of division.
>  
> http://archives.postgresql.org/pgsql-bugs/2010-03/msg00233.php
> http://archives.postgresql.org/pgsql-bugs/2010-03/msg00241.php
> http://archives.postgresql.org/pgsql-bugs/2010-03/msg00244.php
> http://archives.postgresql.org/pgsql-bugs/2010-03/msg00245.php
> http://archives.postgresql.org/pgsql-bugs/2010-04/msg00006.php

I read most of these messages rather as advocating the use of NUMERIC.

Also, the multiplication problem can be addressed by adding a money *
numeric operator.