Re: Bug / feature request for floating point to string conversion

Daniel Frey <d(dot)frey(at)gmx(dot)de> writes:
> INSERT INTO dummy VALUES ( '0X1P-1022' );

> this value itself is the problem. If I use pg_dump / pg_restore, the restore fails with:

> COPY failed for table "dummy": ERROR: "2.22507385850720138e-308" is out of range for type double precision

> This behavior might depend on the system's implementation of strtod(), I'm using Ubuntu 12.04.

That is definitely a bug in strtod, which you should report. If it
doesn't accept a value that sprintf output, something is broken at the
libc level.

> While the problem occurs when importing the data back, the root (IMHO) is, that I can not request floating point values (datatypes REAL and DOUBLE PRECISION) to be returned as strings with the hexadecimal notation (which would easily preserve all bits).

That's not much of a solution from our standpoint, because it assumes
that every platform has such a feature (and that they all agree on what
the hex notation means).

regards, tom lane