PostgreSQL

schemaname name (references pg_namespace.nspname)

Name of schema containing table

tablename name (references pg_class.relname)

Name of table

statistics_schemaname name (references pg_namespace.nspname)

Name of schema containing extended statistic

statistics_name name (references pg_statistic_ext.stxname)

Name of extended statistics

statistics_owner name (references pg_authid.rolname)

Owner of the extended statistics

attnames name[] (references pg_attribute.attname)

Names of the columns the extended statistics is defined on

kinds char[]

Types of extended statistics enabled for this record

n_distinct pg_ndistinct

N-distinct counts for combinations of column values. If greater than zero, the estimated number of distinct values in the combination. If less than zero, the negative of the number of distinct values divided by the number of rows. (The negated form is used when ANALYZE believes that the number of distinct values is likely to increase as the table grows; the positive form is used when the column seems to have a fixed number of possible values.) For example, -1 indicates a unique combination of columns in which the number of distinct combinations is the same as the number of rows.

dependencies pg_dependencies

Functional dependency statistics

most_common_vals text[]

A list of the most common combinations of values in the columns. (Null if no combinations seem to be more common than any others.)

most_common_val_nulls bool[]

A list of NULL flags for the most common combinations of values. (Null when most_common_vals is.)

most_common_freqs float8[]

A list of the frequencies of the most common combinations, i.e., number of occurrences of each divided by total number of rows. (Null when most_common_vals is.)

most_common_base_freqs float8[]

A list of the base frequencies of the most common combinations, i.e., product of per-value frequencies. (Null when most_common_vals is.)