Re: pg_upgrade - link mode and transaction-wraparound data loss

jesper@krogh.cc wrote:
> First the new one..
> 
> jk@pal:~$ psql -p 5433
> psql (9.0beta1)
> Type "help" for help.
> 
> data=# SELECT datname, datfrozenxid FROM pg_database;
>   datname  | datfrozenxid
> -----------+--------------
>  template0 |          654
>  postgres  |   2374592801
>  data      |   2023782337
>  jk        |   2023822188
>  template1 |   2374592801
>  workqueue |   2023822188
> (6 rows)
> 
> data=#         SELECT txid_current();
>  txid_current
> --------------
>    2375384556
> (1 row)

I just ran a test and all the datfrozenxids are less than the current
xid, so the only database that could be generating a wraparound warning
is 'template0'.  But, again, I though that template0 was not touched for
wraparound protection --- I am starting to think I am wrong.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com