From 1887f2ed8cc16a00c60bf72533a8bb195c040faf Mon Sep 17 00:00:00 2001 From: Alexander Korotkov Date: Sat, 25 Nov 2023 00:38:05 +0200 Subject: [PATCH 1/2] Update comments for pg_statistic catalog table Make a reminder that pg_stats view needs to be modified whenever a new slot kind is added. To prevent situations like 918eee0c49 when pg_stats was forgotten to be updated. Also, revise the comment that only non-null, non-empty rows are considered for the range length histogram. 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 --- src/include/catalog/pg_statistic.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/src/include/catalog/pg_statistic.h b/src/include/catalog/pg_statistic.h index 0808c5fc893..87f48dc6894 100644 --- a/src/include/catalog/pg_statistic.h +++ b/src/include/catalog/pg_statistic.h @@ -152,6 +152,9 @@ DECLARE_FOREIGN_KEY((starelid, staattnum), pg_attribute, (attrelid, attnum)); * data "kind" will appear in any particular slot. Instead, search the * stakind fields to see if the desired data is available. (The standard * function get_attstatsslot() may be used for this.) + * + * Note: The pg_stats view needs to be modified whenever a new slot kind is + * added to core. */ /* @@ -262,7 +265,8 @@ DECLARE_FOREIGN_KEY((starelid, staattnum), pg_attribute, (attrelid, attnum)); * a format similar to STATISTIC_KIND_HISTOGRAM: it contains M (>=2) range * values that divide the column data values into M-1 bins of approximately * equal population. The lengths are stored as float8s, as measured by the - * range type's subdiff function. Only non-null rows are considered. + * range type's subdiff function. Only non-null, non-empty rows are + * considered. */ #define STATISTIC_KIND_RANGE_LENGTH_HISTOGRAM 6 -- 2.39.3 (Apple Git-145)