Tom,
I got the followign Erorr when i tried to trucate the table.
 /usr/local/pgsql/bin/postgres -D data -O -o standalone_log template0
 
2005-12-26 22:48:12 ERROR:  expected one dependency record for TOAST table, found 0
2005-12-26 22:48:31 ERROR:  could not access status of transaction 1107341112
DETAIL:  could not open file "/home/postgres/data/pg_clog/0420": No such file or directory 
2005-12-26 22:48:41 LOG:  shutting down
2005-12-26 22:48:41 LOG:  database system is shut down
please suggest ?.
 
On 12/26/05, Tom Lane <tgl@sss.pgh.pa.us> wrote:Gourish Singbal <gourish@gmail.com> writes:
> Got the following ERROR when i was vacuuming the template0 database. 
Why were you doing that in the first place?  template0 shouldn't ever
be touched.
> postgresql server version is 7.4.5
The underlying cause is likely related to this 7.4.6 bug fix:
2004-10-13 18:22  tgl 
       * contrib/pgstattuple/pgstattuple.c,
       src/backend/access/heap/heapam.c,
       src/backend/utils/adt/ri_triggers.c (REL7_4_STABLE): Repair
       possible failure to update hint bits back to disk, per 
       http://archives.postgresql.org/pgsql-hackers/2004-10/msg00464.php.
       I plan a more permanent fix in HEAD, but for the back branches it 
       seems best to just touch the places that actually have a problem.
> INFO:  vacuuming "pg_catalog.pg_statistic"
> ERROR:  could not access status of transaction 1107341112
> DETAIL:  could not open file "/home/postgres/data/pg_clog/0420": No such 
> file or directory
Fortunately for you, pg_statistic doesn't contain any irreplaceable
data.  So you could get out of this via
       TRUNCATE pg_statistic;
       VACUUM ANALYZE;  -- rebuild contents of pg_statistic 
       VACUUM FREEZE;   -- make sure template0 needs no further vacuuming
Then reset template0's datallowconn to false, and get rid of that code
to override it.  And then update to a more recent release ;-)
(I don't recall exactly what rules 7.4 uses, but likely you'll find that
you need to run a standalone backend with -O switch to perform
TRUNCATE on a system catalog.)
                       regards, tom lane 
 -- 
Best,
Gourish Singbal