## 52.51. `pg_statistic_ext_data`
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The catalog `pg_statistic_ext_data` holds data for extended planner statistics defined in [`pg_statistic_ext`](catalog-pg-statistic-ext.html). Each row in this catalog corresponds to a *statistics object* created with [`CREATE STATISTICS`](sql-createstatistics.html).
Like [`pg_statistic`](catalog-pg-statistic.html), `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`](view-pg-stats-ext.html) is a publicly readable view on `pg_statistic_ext_data` (after joining with [`pg_statistic_ext`](catalog-pg-statistic-ext.html)) 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`](catalog-pg-statistic-ext.html).`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 |