Range types do not display in pg_stats

create table tstztest( trange tstzrange );

postgres=# insert into tstztest select tstzrange(t, t + interval '1 month')
from generate_series('2012-01-01'::timestamptz,'2018-01-01','1 month')
as gs(t);
INSERT 0 73
postgres=# analyze tstztest;
ANALYZE
postgres=# select * from pg_stats where tablename = 'tstztest';
schemaname | tablename | attname | inherited | null_frac | avg_width |
n_distinct | most_common_vals | most_common_freqs | histogram_bounds
| correlation | most_common_elems | most_common_elem_freqs |
elem_count_histogram
------------+-----------+---------+-----------+-----------+-----------+------------+------------------+-------------------+------------------
+-------------+-------------------+------------------------+----------------------
public | tstztest | trange | f | 0 | 22 |
-1 | | |
| | | |

Now, there actually *is* a histogram for the column, which you can find
via pg_statistic. But is shows up as NULL in pg_stats view.

If this is a known issue, we ought to at least add it to the docs.

--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com