Horton

Re: Statistics Import and Export

jian he <jian.universality@gmail.com>

View thread
From: jian he <jian.universality@gmail.com>
To: Corey Huinker <corey.huinker@gmail.com>
Cc: Jeff Davis <pgsql@j-davis.com>, Michael Paquier <michael@paquier.xyz>, Nathan Bossart <nathandbossart@gmail.com>, Bruce Momjian <bruce@momjian.us>, Matthias van de Meent <boekewurm+postgres@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>, 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>, alvherre@alvh.no-ip.org, Noah Misch <noah@leadboat.com>
Date: 2025-01-21T15:37:13Z
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.

On Tue, Jan 21, 2025 at 2:43 PM Corey Huinker <corey.huinker@gmail.com> wrote:
>
>
>
> On Mon, Jan 20, 2025 at 10:59 PM Corey Huinker <corey.huinker@gmail.com> wrote:
>>>
>>> Are you saying that there is a path for a partitioned index to have
>>> stats today? If so, we can just follow that locking protocol. If not,
>>> I'm concerned about trying to define the locking protocol for doing so
>>> as a side-effect of this work.
>>
>>
>> A quick test on v17 indicates that, no, there is no path for a partitioned index to have stats of its own, so I'm fine with removing RELKIND_PARTITIONED_INDEX from the allowable relkinds. The partitions of the partitioned index have stats but the umbrella index does not.
>>
>>>
>>> Wouldn't it be easy enough to issue a WARNING and skip it?
>>
>>
>> Sure.
>>
>
>
> So this is the next iteration - it rejects setting stats on partitioned indexes entirely, and it does all the ACL checks against the underlying relation instead of the indexrel. The only oddity is that if a user calls a statistics setting function on some_index of some_table, and they do not have permission to modify stats on some_table, the error message they get reflects the lack of permission on some_table, not the some_index that was invoked. That may be initially surprising, but it actually is more helpful because the permissions that need to change are on the table not the index.


    /*
     * For indexes, we follow what do_analyze_rel() does so as to avoid any
     * deadlocks with analyze/vacuum, which is to take out a
     * ShareUpdateExclusive on table/matview first and only after that take
     * a a AccessShareLock on the index itself.
     */
there are two "a a".


 #include "access/relation.h"
+#include "c.h"
+#include "catalog/pg_class_d.h"
 #include "catalog/pg_database.h"
+#include "catalog/index.h"
+#include "storage/lockdefs.h"
+#include "storage/lmgr.h"
 #include "utils/acl.h"
+#include "utils/lsyscache.h"
 #include "utils/rel.h"
+#include "utils/syscache.h"

+#include "c.h", no need. since we have "postgres.h"
+#include "storage/lockdefs.h" no need. because #include
"storage/lmgr.h" already have it.
+#include "utils/syscache.h" no need. because get_rel_relkind is in
``#include "utils/lsyscache.h"``


in pg_class.h we have
#include "catalog/pg_class_d.h" /* IWYU pragma: export */
if i read
https://github.com/include-what-you-use/include-what-you-use/blob/master/docs/IWYUPragmas.md#iwyu-pragma-export
correctly.
here
+#include "catalog/pg_class_d.h"
should be
+#include "catalog/pg_class.h"