52.53. pg_statistic_ext_data #

   The catalog pg_statistic_ext_data holds data for extended planner
   statistics defined in pg_statistic_ext. Each row in this catalog
   corresponds to a statistics object created with CREATE STATISTICS.

   Normally there is one entry, with stxdinherit = false, for each
   statistics object that has been analyzed. If the table has inheritance
   children or partitions, a second entry with stxdinherit = true is also
   created. This row represents the statistics object over the inheritance
   tree, i.e., statistics for the data you'd see with SELECT * FROM
   table*, whereas the stxdinherit = false row represents the results of
   SELECT * FROM ONLY table.

   Like pg_statistic, pg_statistic_ext_data should not be readable by the
   public, since the contents might be considered sensitive. (Example:
   most common combinations of values in columns might be quite
   interesting.) pg_stats_ext is a publicly readable view on
   pg_statistic_ext_data (after joining with pg_statistic_ext) that only
   exposes information about tables the current user owns.

   Table 52.53. pg_statistic_ext_data Columns

   Column Type

   Description

   stxoid oid (references pg_statistic_ext.oid)

   Extended statistics object containing the definition for this data

   stxdinherit bool

   If true, the stats include values from child tables, not just the
   values in the specified relation

   stxdndistinct pg_ndistinct

   N-distinct counts, serialized as pg_ndistinct type

   stxddependencies pg_dependencies

   Functional dependency statistics, serialized as pg_dependencies type

   stxdmcv pg_mcv_list

   MCV (most-common values) list statistics, serialized as pg_mcv_list
   type

   stxdexpr pg_statistic[]

   Per-expression statistics, serialized as an array of pg_statistic type