On 15 Dec 2018, at 10:15am, Frank Millman <fr...@chagford.com> wrote:
> Simon Slavin says ‘Currency amounts should be stored as integers’. Does this > apply to sqlite3 specifically, or is that your recommendation for all > databases? For anything that goes near a computer. I used to work with international banking software. Any time we put out a tender for an interface and the bidder treated currencies as REAL we knew we'd be able to find a calculation which invisibly lost or gained a fraction. Even with division we could trip up their software. It's an inherent problem with using binary operations on a base-10 fraction. The only time you treat currency units as real is when you're doing calculations which are inherently real. As when you're given a yearly interest rate of 4% and want to know how much interest you'd get for 820 days. And even with that you do the calculation and convert the answer to an integer, using whatever rounding/truncating algorithm your banking authority has approved. It doesn't involve much less work once you've decided to do it. The big problem occurs only when taking a system which was designed (possibly by someone else years ago) for fractions and converting all the data. Simon. _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
