Re: Ryu floating point output patch

From: Andrew Gierth <andrew(at)tao11(dot)riddles(dot)org(dot)uk>
To: pgsql-hackers(at)postgresql(dot)org
Cc: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, "David G(dot) Johnston" <david(dot)g(dot)johnston(at)gmail(dot)com>, Donald Dong <xdong(at)csumb(dot)edu>, Andres Freund <andres(at)anarazel(dot)de>, Robert Haas <robertmhaas(at)gmail(dot)com>, Chapman Flack <chap(at)anastigmatix(dot)net>
Subject: Re: Ryu floating point output patch
Date: 2019-02-13 17:09:03
Message-ID: 877ee3pqm4.fsf@news-spur.riddles.org.uk
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

>>>>> "Andrew" == Andrew Gierth <andrew(at)tao11(dot)riddles(dot)org(dot)uk> writes:

Andrew> 2. How far do we need to go to support existing uses of
Andrew> extra_float_digits? For example, do we need a way for clients to
Andrew> request that they get the exact same output as previously for
Andrew> extra_float_digits=2 or 3, rather than just assuming that any
Andrew> round-trip-exact value will do?

Andrew> (this would likely mean adding a new GUC, rather than basing
Andrew> everything off extra_float_digits as the patch does now)

So it turns out, for reasons that should have been obvious in advance,
that _of course_ we need this, because otherwise there's no way to do
the cross-version upgrade regression check.

So we need something like exact_float_output='on' (default) that can be
selectively set to 'off' to restore the previous behavior of
extra_float_digits.

Thoughts?

--
Andrew (irc:RhodiumToad)

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Magnus Hagander 2019-02-13 17:09:40 Re: Reaping Temp tables to avoid XID wraparound
Previous Message Tom Lane 2019-02-13 17:05:18 Re: Reaping Temp tables to avoid XID wraparound