Horton

Re: Statistics Import and Export

jian he <jian.universality@gmail.com>

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From: jian he <jian.universality@gmail.com>
To: Jeff Davis <pgsql@j-davis.com>
Cc: Corey Huinker <corey.huinker@gmail.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: 2024-08-27T03:35:00Z
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.

On Sat, Aug 24, 2024 at 4:50 AM Jeff Davis <pgsql@j-davis.com> wrote:
>
>
> I have attached version 28j as one giant patch covering what was
> previously 0001-0003. It's a bit rough (tests in particular need some
> work), but it implelements the logic to replace only those values
> specified rather than the whole tuple.
>
hi.
I did some review for v28j

git am shows some whitespace error.


+extern Datum pg_set_relation_stats(PG_FUNCTION_ARGS);
+extern Datum pg_set_attribute_stats(PG_FUNCTION_ARGS);
is unnecessary?


+       <entry role="func_table_entry">
+        <para role="func_signature">
+         <indexterm>
+          <primary>pg_set_relation_stats</primary>
+         </indexterm>
+         <function>pg_set_relation_stats</function> (
+         <parameter>relation</parameter> <type>regclass</type>
+         <optional>, <parameter>relpages</parameter>
<type>integer</type></optional>
+         <optional>, <parameter>reltuples</parameter>
<type>real</type></optional>
+         <optional>, <parameter>relallvisible</parameter>
<type>integer</type></optional> )
+         <returnvalue>boolean</returnvalue>
+        </para>
+        <para>
+         Updates table-level statistics for the given relation to the
+         specified values. The parameters correspond to columns in <link
+         linkend="catalog-pg-class"><structname>pg_class</structname></link>.
Unspecified
+         or <literal>NULL</literal> values leave the setting
+         unchanged. Returns <literal>true</literal> if a change was made;
+         <literal>false</literal> otherwise.
+        </para>
are these <optional> flags wrong? there is only one function currently:
pg_set_relation_stats(relation regclass, relpages integer, reltuples
real, relallvisible integer)
i think you want
pg_set_relation_stats(relation regclass, relpages integer default
null, reltuples real default null, relallvisible integer default null)
we can add following in src/backend/catalog/system_functions.sql:

select * from pg_set_relation_stats('emp'::regclass);
CREATE OR REPLACE FUNCTION
  pg_set_relation_stats(
                        relation regclass,
                        relpages integer default null,
                        reltuples real default null,
                        relallvisible integer default null)
RETURNS bool
LANGUAGE INTERNAL
CALLED ON NULL INPUT VOLATILE
AS 'pg_set_relation_stats';


typedef enum ...
need to add src/tools/pgindent/typedefs.list


+/*
+ * Check that array argument is one dimensional with no NULLs.
+ *
+ * If not, emit at elevel, and set argument to NULL in fcinfo.
+ */
+static void
+check_arg_array(FunctionCallInfo fcinfo, struct arginfo *arginfo,
+ int argnum, int elevel)
+{
+ ArrayType  *arr;
+
+ if (PG_ARGISNULL(argnum))
+ return;
+
+ arr = DatumGetArrayTypeP(PG_GETARG_DATUM(argnum));
+
+ if (ARR_NDIM(arr) != 1)
+ {
+ ereport(elevel,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("\"%s\" cannot be a multidimensional array",
+ arginfo[argnum].argname)));
+ fcinfo->args[argnum].isnull = true;
+ }
+
+ if (array_contains_nulls(arr))
+ {
+ ereport(elevel,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+ errmsg("\"%s\" array cannot contain NULL values",
+ arginfo[argnum].argname)));
+ fcinfo->args[argnum].isnull = true;
+ }
+}
this part elevel should always be ERROR?
if so, we can just
+ ereport(ERROR,
+ (errcode(ERRCODE_INVALID_PARAMETER_VALUE),




relation_statistics_update and other functions
may need to check relkind?
since relpages, reltuples, relallvisible not meaning to all of relkind?