Re: 8.3: timestamp subtraction

On 2009-05-23, Havasvölgyi Ottó <havasvolgyi.otto@gmail.com> wrote:
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> Hi,
>
> I don't know why this query returns false:
>
> SELECT '20040506 070809.010000'::timestamp(6) - '20010203
> 040506.007000'::timestamp(6) = '1188 day 3 hour 3 minute 3 second 3
> millisecond'::interval;
> If I just subtract the two timestamps, its result is the interval I
> specified.
>
> What may cause this?

floating point arithmetic.

especially floats involving fractions.