Re: Do we force dependency? - Mailing list pgsql-hackers

From Qingqing Zhou
Subject Re: Do we force dependency?
Date
Msg-id d80coa$1bjs$1@news.hub.org
Whole thread Raw
In response to Do we force dependency?  (Qingqing Zhou <zhouqq@cs.toronto.edu>)
Responses Re: Do we force dependency?
List pgsql-hackers
"Tom Lane" <tgl@sss.pgh.pa.us> writes
>
> Deletion scans the entries and either deletes the dependent objects or
> raises error.  It's not "by hand" particularly, at least not for
> anything outside dependency.c.  If you were to write code that deleted
> objects directly without going through the dependency mechanism, it
> wouldn't get accepted ;-)
>

The reason I raise this question is because I corrupted pg_trigger by
concurrently perform drop/create table (with foreign keys). This was posted
in pgbugs, but it is weird that I can't find out the original post. I
suspect there are some race conditions in object deletion but not sure
where:

test=# select * from pg_trigger where tgconstrrelid not in (select oid from
pg_class);tgrelid |           tgname           | tgfoid | tgtype | tgenabled |
tgisconstraint |  tgconstrname  | tgconstrrelid | tgdeferrable |
tginitdeferred |
tgnargs| tgattr |                              tgargs
---------+----------------------------+--------+--------+-----------+-------
----
-----+----------------+---------------+--------------+----------------+-----
----
+--------+------------------------------------------------------------------
-   1260 | pg_sync_pg_pwd             |   1689 |     29 | t         | f    |                |             0 | f
  | f              |
 
0
|        |   1261 | pg_sync_pg_group           |   1689 |     29 | t         | f    |                |             0 |
f           | f              |
 
0
|        |  21598 | RI_ConstraintTrigger_21603 |   1644 |     21 | t         | t    | t_ds_col1_fkey |         21594 |
f           | f              |
 
6
|        | t_ds_col1_fkey\000t_ds\000t_wr\000UNSPECIFIED\000col1\000col1\000
(3 rows)



Regards,
Qingqing






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