Re: Dropping constraints on a table locks referenced table... why? - Mailing list pgsql-admin

From Tom Lane
Subject Re: Dropping constraints on a table locks referenced table... why?
Date
Msg-id 8704.1524076765@sss.pgh.pa.us
Whole thread Raw
In response to Re: Dropping constraints on a table locks referenced table... why?  (Wells Oliver <wells.oliver@gmail.com>)
List pgsql-admin
Wells Oliver <wells.oliver@gmail.com> writes:
> Where can I see these triggers? They don't show under the PG Admin trigger
> tab of course, are they, I don't know, special triggers, stored elsewhere?
> Can I query an internal PG table?

Sure, like this:

regression=# create table pk (f1 int primary key);
CREATE TABLE
regression=# create table fk (f1 int references pk);
CREATE TABLE
regression=# select tgname,tgfoid::regproc from pg_trigger where tgrelid = 'pk'::regclass;
            tgname            |         tgfoid
------------------------------+------------------------
 RI_ConstraintTrigger_a_51649 | "RI_FKey_noaction_del"
 RI_ConstraintTrigger_a_51650 | "RI_FKey_noaction_upd"
(2 rows)

regression=# select tgname,tgfoid::regproc from pg_trigger where tgrelid = 'fk'::regclass;
            tgname            |       tgfoid
------------------------------+---------------------
 RI_ConstraintTrigger_c_51651 | "RI_FKey_check_ins"
 RI_ConstraintTrigger_c_51652 | "RI_FKey_check_upd"
(2 rows)

psql and probably most other client tools hide these triggers figuring
they're uninteresting, but they're pretty ordinary triggers otherwise.

            regards, tom lane


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