Horton

Re: Ryu floating point output patch

Andrew Dunstan <andrew.dunstan@2ndquadrant.com>

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From: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
To: Andrew Gierth <andrew@tao11.riddles.org.uk>, Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-hackers@postgresql.org, "David G. Johnston" <david.g.johnston@gmail.com>, Donald Dong <xdong@csumb.edu>, Andres Freund <andres@anarazel.de>, Robert Haas <robertmhaas@gmail.com>, Chapman Flack <chap@anastigmatix.net>
Date: 2019-02-17T23:21:56Z
Lists: pgsql-hackers 
On 2/17/19 6:15 PM, Andrew Gierth wrote:
>>>>>> "Tom" == Tom Lane <tgl@sss.pgh.pa.us> writes:
>  > Andrew Dunstan <andrew.dunstan@2ndquadrant.com> writes:
>  >> Here's a patch without docco. How much do we actually want to
>  >> document this? I'm not sure it has any great value outside of
>  >> cross-version upgrade testing.
>
>  Tom> I think we have to document it, but it can be fairly terse perhaps.
>
>  Tom> 	Use the specified value of extra_float_digits when dumping
>  Tom> 	floating-point data, rather than pg_dump's default.
>
>  Tom> I don't think we need to go into detail about when/why you might
>  Tom> want to use it; I can see people thinking of their own reasons.
>
> It should probably at least say that (a) the default is to dump with the
> maximum available precision, and at least hint at (b) that ordinary use
> doesn't require the option. We shouldn't mislead people into thinking
> they need it when they don't.
>

Would you like to reformulate this, then?


cheers


andrew

-- 
Andrew Dunstan                https://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services

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.