Re: BUG #16045: vacuum_db crash and illegal memory alloc after pg_upgrade from PG11 to PG12

Tomas Vondra <tomas.vondra@2ndquadrant.com>

From: Tomas Vondra <tomas.vondra@2ndquadrant.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Andres Freund <andres@anarazel.de>, buschmann@nidsa.net, pgsql-bugs@lists.postgresql.org
Date: 2019-10-13T20:38:48Z
Lists: pgsql-bugs, pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Move into separate file all the SQL queries used in pg_upgrade tests

  2. Add table to regression tests for binary-compatibility checks in pg_upgrade

  3. Fix tests of pg_upgrade across different major versions

  4. Multirange datatypes

  5. Work around cross-version-upgrade issues created by commit 9e38c2bb5.

  6. Declare assorted array functions using anycompatible not anyelement.

  7. Remove factorial operators, leaving only the factorial() function.

  8. Create by default sql/ and expected/ for output directory in pg_regress

  9. Add missing include to pg_upgrade/version.c

  10. Improve the check for pg_catalog.line data type in pg_upgrade

  11. Improve the check for pg_catalog.unknown data type in pg_upgrade

  12. Check for tables with sql_identifier during pg_upgrade

  13. pg_upgrade: clarify the database names in error files

  14. In the pg_upgrade test suite, don't write to src/test/regress.

  15. Allow group access on PGDATA

  16. Refactor dir/file permissions

  17. Remove unused functions in regress.c.

  18. Make WAL segment size configurable at initdb time.

  19. Fix bit-rot in pg_upgrade's test.sh, and improve documentation.

On Sun, Oct 13, 2019 at 02:26:48PM -0400, Tom Lane wrote:
>Tomas Vondra <tomas.vondra@2ndquadrant.com> writes:
>> here is an updated patch, with the recursive CTE. I've done a fair
>> amount of testing on it on older versions (up to 9.4), and it seems to
>> work just fine.
>
>Might be a good idea to exclude attisdropped columns in the part of the
>recursive query that's looking for sql_identifier columns of composite
>types.  I'm not sure if composites can have dropped columns today,
>but even if they can't it seems like a wise bit of future-proofing.
>(We'll no doubt have occasion to use this logic again...)
>

Hmm? How could that be safe? Let's say we have a composite type with a
sql_identifier column, it's used in a table with data, and we drop the
column. We need the pg_type information to parse the existing, so how
could we skip attisdropped columns?

>Looks good other than that nit.
>
>> BTW the query (including the RELKIND_COMPSITE_TYPE) was essentially just
>> a lightly-massaged copy of old_9_6_check_for_unknown_data_type_usage, so
>> that seems wrong too.
>
>Yeah, we should back-port this logic into that check too, IMO.
>

You mean the recursive CTE, removal of RELKIND_COMPOSITE_TYPE or the
proposed change w.r.t. dropped columns?


regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
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