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From: Tom Lane <tgl@sss.pgh.pa.us>
To: pgsql-hackers@lists.postgresql.org
Subject: Instability in parallel regression tests
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guaibasaurus just failed in a way I'd not seen before:

https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=3Dguaibasaurus&dt=3D=
2018-03-14%2006%3A33%3A01

Inspection of the diffs makes it depressingly obvious what happened:
the concurrently-executing "alter_table" and "with" scripts both create
short-lived tables named "test".  Given the right timing, those tests
stomp on each other.  This seems to have been there a long time;
surprising we'd not noticed it before.

Moral: choose names less generic than "test" for globally-visible
objects.  I wonder if there's some way we could check for such
conflicts automatically?

			regards, tom lane