Re: Test to dump and restore objects left behind by regression

> On 22 Feb 2024, at 10:16, Peter Eisentraut <peter@eisentraut.org> wrote:

> We have somewhat relied on the pg_upgrade test to provide this testing, but we have recently discovered that the
dumpsin binary-upgrade mode are different enough to not test the normal dumps well. 
>
> Yes, this test is a bit expensive.  We could save some time by doing the first dump at the end of the normal regress
testand have the pg_dump test reuse that, but then that would make the regress test run a bit longer.  Is that a better
tradeoff?

Something this expensive seems like what PG_TEST_EXTRA is intended for, we
already have important test suites there.

But.  We know that the cluster has an interesting state when the pg_upgrade
test starts, could we use that to make a dump/restore test before continuing
with testing pg_upgrade?  It can be argued that pg_upgrade shouldn't be
responsible for testing pg_dump, but it's already now a pretty important
testcase for pg_dump in binary upgrade mode so it's that far off.  If pg_dump
has bugs then pg_upgrade risks subtly breaking.

When upgrading to the same version, we could perhaps also use this to test a
scenario like: Dump A, restore into B, upgrade B into C, dump C and compare C
to A.

--
Daniel Gustafsson