Re: Statistics Import and Export

Corey Huinker <corey.huinker@gmail.com>

From: Corey Huinker <corey.huinker@gmail.com>
To: Jeff Davis <pgsql@j-davis.com>
Cc: 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: 2024-07-23T21:48:57Z
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.

Giving the parameter lists more thought, the desire for a return code more
granular than true/false/null, and the likelihood that each function will
inevitably get more parameters both stats and non-stats, I'm proposing the
following:

Two functions:

pg_set_relation_stats(
    out schemaname name,
    out relname name,
    out row_written boolean,
    out params_rejected text[],
    kwargs any[]) RETURNS RECORD

and

pg_set_attribute_stats(
    out schemaname name,
    out relname name,
    out inherited bool,
    out row_written boolean,
    out params_accepted text[],
    out params_rejected text[],
    kwargs any[]) RETURNS RECORD

The leading OUT parameters tell us the rel/attribute/inh affected (if any),
and which params had to be rejected for whatever reason. The kwargs is the
variadic key-value pairs that we were using for all stat functions, but now
we will be using it for all parameters, both statistics and control, the
control parameters will be:

relation - the oid of the relation
attname - the attribute name (does not apply for relstats)
inherited - true false for attribute stats, defaults false, does not apply
for relstats
warnings, boolean, if supplied AND set to true, then all ERROR that can be
stepped down to WARNINGS will be. This is "binary upgrade mode".
version - the numeric version (a la PG_VERSION_NUM) of the statistics
given. If NULL or omitted assume current PG_VERSION_NUM of server.
actual stats columns.

This allows casual users to set only the params they want for their needs,
and get proper errors, while pg_upgrade can set

'warnings', 'true', 'version', 120034

and get the upgrade behavior we need.











 and pg_set_attribute_stats.
    pg_set_relation_stats(out schemaname name, out relname name,, out
row_written boolean, out params_entered int, out params_accepted int,
kwargs any[])