52.51. 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.

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 those tables and columns that are readable by the current user.

Table 52.51. pg_statistic_ext_data Columns

Column Type Description
stxoid oid (references pg_statistic_ext.oid) Extended statistics object containing the definition for this data
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