Re: pg_upgrade automatic testing

Peter Eisentraut wrote:
> But if you think about it, it doesn't really test pg_upgrade, it tests
> pg_dump.  So the test could just as well be moved to src/bin/pg_dump/
> and be labeled "pg_dump smoke test" or whatever.  (Minor detail: The bug
> fix above involved the --binary-upgrade flag, so it is somewhat
> pg_upgrade related.)
> 
> A real pg_upgrade test suite should naturally upgrade across binary
> incompatible versions.  The real question is how you develop a useful
> test input.  Most pg_upgrade issues are not bugs of omission or
> regression but unexpected corner cases discovered with databases of
> nontrivial usage patterns.  (The recent one related to upgrade from 8.3
> is an exception.)  Because the basic premise of pg_upgrade is, dump and
> restore the schema, move over the files, that's it, and the rest of the
> code is workarounds for obscure details that are difficult to anticipate
> let alone test for.

You might want to read my blog entry on why pg_upgrade relies so much on
external tools:

	http://momjian.us/main/blogs/pgblog/2011.html#June_15_2011_2

-- 
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + It's impossible for everything to be true. +