Re: Getting Primary & Foreign Key Information?

Here are copies of two responses I received recently when I posted a similar
question.

------- reply from Dominic J. Eidson ----------------------------
The following was posted to the list a while ago, compliments of Michael
Fork:

SELECT pt.tgargs, pt.tgnargs, pt.tgdeferrable, pt.tginitdeferred,
pg_proc.proname, pg_proc_1.proname FROM pg_class pc,
pg_proc pg_proc, pg_proc pg_proc_1, pg_trigger pg_trigger,
pg_trigger pg_trigger_1, pg_proc pp, pg_trigger pt
WHERE pt.tgrelid = pc.oid AND pp.oid = pt.tgfoid
AND pg_trigger.tgconstrrelid = pc.oid
AND pg_proc.oid = pg_trigger.tgfoid
AND pg_trigger_1.tgfoid = pg_proc_1.oid
AND pg_trigger_1.tgconstrrelid = pc.oid
AND ((pc.relname= '<< TABLENAME >>>')
AND (pp.proname LIKE '%%ins')
AND (pg_proc.proname LIKE '%%upd')
AND (pg_proc_1.proname LIKE '%%del')
AND (pg_trigger.tgrelid=pt.tgconstrrelid)
AND (pg_trigger_1.tgrelid = pt.tgconstrrelid));

This will show all foreign keys on a table.

-- reply from-----------------------------------------
-- "Jim Buttafuoco"<jim(at)spectrumtelecorp(dot)com> ---------------

I use the following PLPERL/select "code" to view all FK's in my database
.. I guess the "select" could be made into a pg_fkeys view. What do
people think...

Just a note. I used PLPERL because the fkey data is stored in a BYTEA
data field and other then a "C" function PLPERL works fine for me...

Let me know if it works for you..
Jim

--
-- I called this function "j" during development and never changed
-- it.
--
CREATE FUNCTION j(bytea,varchar) RETURNS text AS '

@data = split(/\\\\000/, $_[0]);

$a = $data[0] if $_[1] eq "FKNAME";
$a = $data[1] if $_[1] eq "FTAB";
$a = $data[2] if $_[1] eq "TTAB";
$a = join(",",(@data)[4,6,8,10,12,14]) if $_[1] eq "FCOLS";
$a = join(",",(@data)[5,7,9,11,13,15]) if $_[1] eq "TCOLS";

$a =~ s/,+$//g;
return $a;
' LANGUAGE 'plperl';

select a.tgconstrname,
j(tgargs,'FTAB'::varchar) || '(' || j(tgargs,'FCOLS'::varchar)
|| ')' as from,

j(tgargs,'TTAB'::varchar) || '(' || j(tgargs,'TCOLS'::varchar)
|| ')' as references

,
cd as "cascade_delete",
cu as cascade_update
from ( pg_trigger a left join
(select tgconstrname,'Y' as cd from pg_trigger where tgfoid = 1646) b on
(a.tgconstrname =
b.tgconstrname) )
left join
(select tgconstrname,'Y' as cu from pg_trigger where tgfoid = 1647) c on
(a.tgconstrname =
b.tgconstrname)
where
tgfoid = 1644
and
tgisconstraint;

Hope this helps you.
Mike

===================
Mike Finn
Tactical Executive Systems
mike(dot)finn(at)tacticalExecutive(dot)com