pg_constraint missing many entries?

Almost all of my foreign key definitions are NOT present in
pg_constraint. However, they do exist as triggers. It appears that *new*
foreign keys, whether defined in new tables or added on via "ALTER
TABLE" commands, make it into pg_constraint, but the "old" stuff that
was present from before our 7.3 upgrade, exists only as triggers.

1) Is this a bug?

2) Is there any way to "refresh" pg_constraint? (I'm experimenting with
a tool that graphs a schema, and it needs a bit of code written to
determine from a table and column name whether that column is a foreign
key, and to what table. pg_constraint where contype = 'f' seems to be
the ticket, but on my database it's inadequate.)

--
Jeff Boes vox 269.226.9550 ext 24
Database Engineer fax 269.349.9076
Nexcerpt, Inc. http://www.nexcerpt.com
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