Incorrect rounding of double values at max precision

Hi,

When storing a double in Postgres, it looks like under specific circumstances it can get rounded incorrectly:

select round(cast(float8 '42258656681.38498' as numeric), 2), round(numeric '42258656681.38498', 2);

which returns either 42258656681.38 or 42258656681.39 depending on whether it is float8 or not.

Thanks,

Gilleain

Gilleain Torrance
Consultant

Alfa
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