Horton

Re: Statistics Import and Export

jian he <jian.universality@gmail.com>

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From: jian he <jian.universality@gmail.com>
To: Corey Huinker <corey.huinker@gmail.com>
Cc: Jeff Davis <pgsql@j-davis.com>, Matthias van de Meent <boekewurm+postgres@gmail.com>, Bruce Momjian <bruce@momjian.us>, Tom Lane <tgl@sss.pgh.pa.us>, Nathan Bossart <nathandbossart@gmail.com>, Magnus Hagander <magnus@hagander.net>, Stephen Frost <sfrost@snowman.net>, Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>, Peter Smith <smithpb2250@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, Tomas Vondra <tomas.vondra@enterprisedb.com>, alvherre@alvh.no-ip.org
Date: 2024-09-08T02:02:00Z
Lists: 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. Change pg_dump default for statistics export.

  2. pg_dump: Adjust reltuples from 0 to -1 for dumps of older versions.

  3. vacuumdb: Don't skip empty relations in --missing-stats-only mode.

  4. pg_dump: Fix query for gathering attribute stats on older versions.

  5. Prevent redeclaration of typedef TocEntry.

  6. Remove unused function parameters in pg_backup_archiver.c.

  7. pg_dump: Retrieve attribute statistics in batches.

  8. pg_dump: Reduce memory usage of dumps with statistics.

  9. Skip second WriteToc() call for custom-format dumps without data.

  10. Add relallfrozen to pg_dump statistics.

  11. Matview statistics depend on matview data.

  12. Add pg_dump --with-{schema|data|statistics} options.

  13. Stats: use schemaname/relname instead of regclass.

  14. CREATE INDEX: do update index stats if autovacuum=off.

  15. Don't convert to and from floats in pg_dump.

  16. CREATE INDEX: don't update table stats if autovacuum=off.

  17. Organize and deduplicate statistics import tests.

  18. Address stats export review comments.

  19. Address stats import review comments.

  20. Add relallfrozen to pg_class

  21. Fix pg_strtof() to not crash on NULL endptr.

  22. Use attnum to identify index columns in pg_restore_attribute_stats().

  23. pg_dump: prepare attribute stats query.

  24. Avoid unnecessary relation stats query in pg_dump.

  25. Remove redundant pg_set_*_stats() variants.

  26. Do not use in-place updates for statistics import.

  27. Fix confusion about data type of pg_class.relpages and relallvisible.

  28. Documentation fixups for dumping statistics.

  29. Trial fix for old cross-version upgrades.

  30. Transfer statistics during pg_upgrade.

  31. Lock table in ShareUpdateExclusive when importing index stats.

  32. Use in-place updates for pg_restore_relation_stats().

  33. Improve error message for replication of generated columns.

  34. pg_dump: Add dumpSchema and dumpData derivative flags.

  35. Disallow modifying statistics on system columns.

  36. Add missing CommandCounterIncrement() in stats import functions.

  37. Add functions pg_restore_relation_stats(), pg_restore_attribute_stats().

  38. Documentation fixup.

  39. Add functions pg_set_attribute_stats() and pg_clear_attribute_stats().

  40. Change pg_*_relation_stats() functions to return type to void.

  41. Disable autovacuum for tables in stats import tests.

  42. Allow pg_set_relation_stats() to set relpages to -1.

  43. Fixup for pg_set_relation_stats().

  44. Create functions pg_set_relation_stats, pg_clear_relation_stats.

  45. Add memory/disk usage for Window aggregate nodes in EXPLAIN.

  46. Improve performance of dumpSequenceData().

  47. Add INJECTION_POINT_CACHED() to run injection points directly from cache

  48. Improve performance of binary_upgrade_set_pg_class_oids().

  49. Improve assertion in mdwritev()

  50. CREATE INDEX: do not update stats during binary upgrade.

  51. Redefine pg_class.reltuples to be -1 before the first VACUUM or ANALYZE.

Attachments

On Fri, Sep 6, 2024 at 1:34 AM Corey Huinker <corey.huinker@gmail.com> wrote:
>>
>>
>> this part elevel should always be ERROR?
>> if so, we can just
>
>
> I'm personally dis-inclined to error on any of these things, so I'll be leaving it as is. I suspect that the proper balance lies between all-ERROR and all-WARNING, but time will tell which.
>
somehow, i get it now.


>>
>> relation_statistics_update and other functions
>> may need to check relkind?
>> since relpages, reltuples, relallvisible not meaning to all of relkind?
>
>
> I'm not able to understand either of your questions, can you elaborate on them?
>

Please check my attached changes.
also see the attached cf-bot commit message.

1. make sure these three functions: 'pg_set_relation_stats',
'pg_restore_relation_stats','pg_clear_relation_stats' proisstrict to true.
because in
pg_class catalog, these three attributes (relpages, reltuples, relallvisible) is
marked as not null. updating it to null will violate these constraints.
tom also mention this at [

2.refactor relation_statistics_update. first sanity check first argument
("relation").
not all kinds of relation can pass on
relation_statistics_update, for example view. so do the sanity check.
also do sanity check for the remaining 3 arguments.
if not ok, ereport(elevel...), return false immediately.

3.add some tests for partitioned table, view, and materialized view.

4. minor sanity check output of "attnum = get_attnum(reloid,
NameStr(*attname));"

5.
create table t(a int, b int);
alter table t drop column b;
SELECT pg_catalog.pg_set_attribute_stats(
relation => 't'::regclass,
attname => 'b'::name,
inherited => false::boolean,
null_frac => 0.1::real,
avg_width => 2::integer,
n_distinct => 0.3::real);

ERROR:  attribute 0 of relation with OID 34316 does not exist
The error message is not good, i think.
Also, in this case, I think we may need soft errors.
instead of returning ERROR, make it return FALSE would be more ok.

6. there are no "inherited => true::boolean,"
tests for pg_set_attribute_stats.
aslo there are no partitioned table related tests on stats_import.sql.
I think we should add some.

7. the doc output, functions-admin.html, there are 4 same warnings.
Maybe one is enough?

8. lock_check_privileges function issue.
------------------------------------------------
--asume there is a superuser jian
create role alice NOSUPERUSER LOGIN;
create role bob NOSUPERUSER LOGIN;
create role carol NOSUPERUSER LOGIN;
alter database test owner to alice
GRANT CONNECT, CREATE on database test to bob;
\c test bob
create schema one;
create table one.t(a int);
create table one.t1(a int);
set session AUTHORIZATION; --switch to superuser.
alter table one.t1 owner to carol;
\c test alice
--now current database owner alice cannot do ANYTHING WITH table one.t1,
like ANALYZE, SELECT, INSERT, MAINTAIN etc.

so i think your relation_statistics_update->lock_check_privileges part is wrong?
also the doc:
"The caller must have the MAINTAIN privilege on the table or be the
owner of the database."
should be
"The caller must have the MAINTAIN privilege on the table or be the
owner of the table"
?