Horton

Re: Ryu floating point output patch

Robert Haas <robertmhaas@gmail.com>

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From: Robert Haas <robertmhaas@gmail.com>
To: Andrew Gierth <andrew@tao11.riddles.org.uk>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Andres Freund <andres@anarazel.de>, Chapman Flack <chap@anastigmatix.net>, "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Date: 2019-01-11T17:55:54Z
Lists: pgsql-hackers 
On Fri, Jan 11, 2019 at 12:33 PM Andrew Gierth
<andrew@tao11.riddles.org.uk> wrote:
> >>>>> "Robert" == Robert Haas <robertmhaas@gmail.com> writes:
>  Robert> I don't have an opinion on the code that is part of this patch
>
> At this point, frankly, I'm less interested in opinions on the code
> itself (which can be addressed later if need be) than on answers to (or
> discussion of) the questions asked upthread.

Unfortunately, I can't help you very much there.  My knowledge is
insufficient to give intelligent answers to those questions, and I
don't think giving you unintelligent answers is a good idea.  About as
much as I can say is that if you commit this patch, and as a result, a
dump-and-restore from v11 to v12 causes a change in the bits on disk
that would not have occurred without this patch, that's very bad.
What ramifications there will be if the output changes in ways that
don't affect the bits that get written to the platter -- I don't know.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company

Commits

  1. Provide an extra-float-digits setting for pg_dump / pg_dumpall

  2. Change floating-point output format for improved performance.

  3. Use strtof() and not strtod() for float4 input.