From 235b2f3de5fff7ae07b0499831435d7b536d6306 Mon Sep 17 00:00:00 2001 From: Alexander Korotkov Date: Sat, 25 Nov 2023 00:38:37 +0200 Subject: [PATCH 2/2] Display length and bounds histograms in pg_stats Values corresponding to STATISTIC_KIND_RANGE_LENGTH_HISTOGRAM and STATISTIC_KIND_BOUNDS_HISTOGRAM were not exposed to pg_stats when these slot kinds were introduced in 918eee0c49. This commit adds the missing fields to pg_stats. Catversion is bumped. Discussion: https://postgr.es/m/flat/b67d8b57-9357-7e82-a2e7-f6ce6eaeec67@postgrespro.ru Author: Egor Rogov, Soumyadeep Chakraborty Reviewed-by: Tomas Vondra, Justin Pryzby, Jian He --- doc/src/sgml/system-views.sgml | 39 ++++++++++++++++++++++++++++ src/backend/catalog/system_views.sql | 23 +++++++++++++++- src/test/regress/expected/rules.out | 26 ++++++++++++++++++- 3 files changed, 86 insertions(+), 2 deletions(-) diff --git a/doc/src/sgml/system-views.sgml b/doc/src/sgml/system-views.sgml index 7078491c4c0..0ef17456318 100644 --- a/doc/src/sgml/system-views.sgml +++ b/doc/src/sgml/system-views.sgml @@ -3799,6 +3799,45 @@ SELECT * FROM pg_locks pl LEFT JOIN pg_prepared_xacts ppx non-null elements. (Null for scalar types.) + + + + range_length_histogram anyarray + + + A histogram of the lengths of non-empty and non-null range values of a + range type column. (Null for non-range types.) + + + This histogram is calculated using the subtype_diff + range function regardless of whether range bounds are inclusive. + + + + + + range_empty_frac float4 + + + Fraction of column entries whose values are empty ranges. + (Null for non-range types.) + + + + + + range_bounds_histogram anyarray + + + A histogram of lower and upper bounds of non-empty and non-null range + values. (Null for non-range types.) + + + These two histograms are represented as a single array of ranges, whose + lower bounds represent the histogram of lower bounds, and upper bounds + represent the histogram of upper bounds. + + diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql index b65f6b52490..11d18ed9dd6 100644 --- a/src/backend/catalog/system_views.sql +++ b/src/backend/catalog/system_views.sql @@ -243,7 +243,28 @@ CREATE VIEW pg_stats WITH (security_barrier) AS WHEN stakind3 = 5 THEN stanumbers3 WHEN stakind4 = 5 THEN stanumbers4 WHEN stakind5 = 5 THEN stanumbers5 - END AS elem_count_histogram + END AS elem_count_histogram, + CASE + WHEN stakind1 = 6 THEN stavalues1 + WHEN stakind2 = 6 THEN stavalues2 + WHEN stakind3 = 6 THEN stavalues3 + WHEN stakind4 = 6 THEN stavalues4 + WHEN stakind5 = 6 THEN stavalues5 + END AS range_length_histogram, + CASE + WHEN stakind1 = 6 THEN stanumbers1[1] + WHEN stakind2 = 6 THEN stanumbers2[1] + WHEN stakind3 = 6 THEN stanumbers3[1] + WHEN stakind4 = 6 THEN stanumbers4[1] + WHEN stakind5 = 6 THEN stanumbers5[1] + END AS range_empty_frac, + CASE + WHEN stakind1 = 7 THEN stavalues1 + WHEN stakind2 = 7 THEN stavalues2 + WHEN stakind3 = 7 THEN stavalues3 + WHEN stakind4 = 7 THEN stavalues4 + WHEN stakind5 = 7 THEN stavalues5 + END AS range_bounds_histogram FROM pg_statistic s JOIN pg_class c ON (c.oid = s.starelid) JOIN pg_attribute a ON (c.oid = attrelid AND attnum = s.staattnum) LEFT JOIN pg_namespace n ON (n.oid = c.relnamespace) diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out index 1442c43d9c5..05070393b99 100644 --- a/src/test/regress/expected/rules.out +++ b/src/test/regress/expected/rules.out @@ -2466,7 +2466,31 @@ pg_stats| SELECT n.nspname AS schemaname, WHEN (s.stakind4 = 5) THEN s.stanumbers4 WHEN (s.stakind5 = 5) THEN s.stanumbers5 ELSE NULL::real[] - END AS elem_count_histogram + END AS elem_count_histogram, + CASE + WHEN (s.stakind1 = 6) THEN s.stavalues1 + WHEN (s.stakind2 = 6) THEN s.stavalues2 + WHEN (s.stakind3 = 6) THEN s.stavalues3 + WHEN (s.stakind4 = 6) THEN s.stavalues4 + WHEN (s.stakind5 = 6) THEN s.stavalues5 + ELSE NULL::anyarray + END AS range_length_histogram, + CASE + WHEN (s.stakind1 = 6) THEN s.stanumbers1[1] + WHEN (s.stakind2 = 6) THEN s.stanumbers2[1] + WHEN (s.stakind3 = 6) THEN s.stanumbers3[1] + WHEN (s.stakind4 = 6) THEN s.stanumbers4[1] + WHEN (s.stakind5 = 6) THEN s.stanumbers5[1] + ELSE NULL::real + END AS range_empty_frac, + CASE + WHEN (s.stakind1 = 7) THEN s.stavalues1 + WHEN (s.stakind2 = 7) THEN s.stavalues2 + WHEN (s.stakind3 = 7) THEN s.stavalues3 + WHEN (s.stakind4 = 7) THEN s.stavalues4 + WHEN (s.stakind5 = 7) THEN s.stavalues5 + ELSE NULL::anyarray + END AS range_bounds_histogram FROM (((pg_statistic s JOIN pg_class c ON ((c.oid = s.starelid))) JOIN pg_attribute a ON (((c.oid = a.attrelid) AND (a.attnum = s.staattnum)))) -- 2.39.3 (Apple Git-145)