Re: How to sum monetary variables

On 18 Jul 2011 at 23:00, Martín Marqués <martin.marques@gmail.com> wrote: > I'm building a table (which is a report that has to be printed) with a > bunch of items (up to 300 in some cases) that have unitary price > (stored in a numeric(9,2) field), how many there are, and the total > price for each item. At the end of the table there is a total of all > the items. > > The app is running on PHP and PostgreSQL is the backend. > > The question is, how do I get the total of everything? > > Running it on PHP gives one value, doing a sum() on the backend gives > another, and I'm starting to notice that even using python as a > calculator gives me errors (big ones). Right now I'm doing the maths > by hand to find out who has the biggest error, or if any is 100% > accurate. Much safer to price everything internally in pence or cents or whatever, and convert to £xxx.xx for external display. Then just use integer arithmetic for the calculations. -- Cheers -- Tim