On Mon, Mar 14, 2016 at 9:29 AM, Merlin Moncure <mmoncure@xxxxxxxxx> wrote: > On Mon, Mar 14, 2016 at 9:21 AM, Pujol Mathieu > <mathieu.pujol@xxxxxxxxxxxxx> wrote: >> Hi >> I reproduce your bug using "PostgreSQL 9.3.6, compiled by Visual C++ build >> 1600, 64-bit" on Windows 8 >> I also notice that SELECT floor(4.725 * power(10, 2)::numeric + 0.5) work as >> expected > > I don't think this is a bug -- just peculiarities of floating point math. To be more clear: the problem is neither with pow() or floor(). The issue is: postgres=# SELECT (4.725 * 100.0 + 0.5 ) = 473; ?column? ────────── t (1 row) Time: 0.387 ms postgres=# SELECT (4.725 * 100.0::FLOAT8 + 0.5 ) = 473; ?column? ────────── f The workaround is to use fixed point or build in epsilon tolerances in any case where you are using decimal numbers and expect precise results. merlin -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
