Re: pg_dump: sortDumpableObjectsByTypeName() doesn't always do that - Mailing list pgsql-hackers

From Jacob Champion
Subject Re: pg_dump: sortDumpableObjectsByTypeName() doesn't always do that
Date
Msg-id CABAq_6F3bn-hg0q2V9GEPUXQwNZu++sWpVsYeEkc7OLBg-S7qw@mail.gmail.com
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In response to Re: pg_dump: sortDumpableObjectsByTypeName() doesn't always do that  (Jacob Champion <pchampion@pivotal.io>)
List pgsql-hackers
On Mon, Aug 6, 2018 at 12:23 PM Jacob Champion <pchampion@pivotal.io> wrote:
> since the
> root cause is that we're not defining a valid ordering, quicksort may
> or may not behave consistently for test purposes.

To expand on this, consider three objects, of the same type, compared
with the current comparator function:

namespace_a.object_3 < namespace_b.object_1 (because a < b)
NULL.object_2 < namespace_a.object_3 (because 2 < 3)
namespace_b.object_1 < NULL.object_2 (because 1 < 2)

This is rock-paper-scissors instead of a partial ordering.

--Jacob


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