Обсуждение: Empty system tables

While looking for tables related to default ops I came across the following
tables that are not mentioned in the programmer docs system catalogues
section and are (in my database anyway) empty.  Perhaps someone who is
closer to the catalogues can confirm that these are still used.  If so,
perhaps we can update the docs to describe them.
 pg_inheritproc pg_listener pg_relcheck

The following tables are used but are not listed in the docs with the
rest.  How about a short description of each?  Maybe even add some to
the diagram.
 pg_attrdef pg_description pg_inherits pg_ipl pg_rewrite pg_shadow pg_statistic pg_trigger

I'm still trying to figure out why I get that fmgr error when I use my
user defined type in a where clause.  Can anyone point me to the tables
that I need to modify?  Here is what I have modified so far.
 pg_opclass pg_amop pg_amproc pg_description

-- 
D'Arcy J.M. Cain <darcy@{druid|vex}.net>   |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 424 2871     (DoD#0082)    (eNTP)   |  what's for dinner.

darcy@druid.net ("D'Arcy" "J.M." Cain) writes:
> perhaps we can update the docs to describe them.

>   pg_listener

pg_listener records which backends are actively listening for NOTIFY
conditions, and is used to transmit NOTIFY signals from one backend to
another.  It will be empty if you do not have any active LISTEN
commands.

>   pg_shadow

Shadow user table, with the real passwords.  (pg_user is actually
only a view of pg_shadow.)

>   pg_statistic

Per-column stats collected by VACUUM ANALYZE and used by the query
optimizer.

Dunno about the rest.
        regards, tom lane