51.51. pg_statistic_ext
The catalog
pg_statistic_ext
holds definitions of extended planner statistics.
Each row in this catalog corresponds to a
statistics object
created with
CREATE STATISTICS
.
Table 51.51.
pg_statistic_ext
Columns
Name  Type  References  Description 

stxrelid

oid


Table containing the columns described by this object 
stxname

name

Name of the statistics object  
stxnamespace

oid


The OID of the namespace that contains this statistics object 
stxowner

oid


Owner of the statistics object 
stxkeys

int2vector


An array of attribute numbers, indicating which table columns are
covered by this statistics object;
for example a value of
1 3
would
mean that the first and the third table columns are covered

stxkind

char[]

An array containing codes for the enabled statistics kinds;
valid values are:
d
for ndistinct statistics,
f
for functional dependency statistics, and
m
for most common values (MCV) list statistics

The
pg_statistic_ext
entry is filled in
completely during
CREATE STATISTICS
, but the actual
statistical values are not computed then.
Subsequent
ANALYZE
commands compute the desired values
and populate an entry in the
pg_statistic_ext_data
catalog.