information schema

Does anybody know why "key_column_usage", and
"referential_constraints" are empty in
information_schema?  Have these been implemented?

e.g.
cms=# select * from
information_schema.key_column_usage;
 constraint_catalog | constraint_schema |
constraint_name | table_catalog | table_schema |
table_name | column_name | ordinal_position

--------------------+-------------------+-----------------+---------------+--------------+------------+-------------+------------------
(0 rows)

cms=# select * from
information_schema.referential_constraints;
 constraint_catalog | constraint_schema |
constraint_name | unique_constraint_catalog |
unique_constraint_schema | unique_constraint_name |
match_option | update_rule | delete_rule

--------------------+-------------------+-----------------+---------------------------+--------------------------+------------------------+--------------+-------------+-------------
(0 rows)

Thanks.

Wei




__________________________________
Do you Yahoo!?
Friends.  Fun.  Try the all-new Yahoo! Messenger.
http://messenger.yahoo.com/