Re: Tables(s) that feed pg_controldata

On 12/09/2018 01:25 AM, Ron wrote:
 >
 > In v9.2 (yes, I know it's EOL; there's nothing I can do about it), what tables
 > do I query to get these values, and can I also get them from the streamed
 > replication host?
 >
 > - Database cluster state
 > - Latest checkpoint location
 > - Time of latest checkpoint

The pg_control file is written directly by PostgreSQL, it does not derive from
any tables.

 From 9.6 there are a bunch of functions which will report values contained in
pg_controldata:

     https://www.postgresql.org/docs/current/functions-info.html#FUNCTIONS-CONTROLDATA

but you're out of luck for 9.2. The only option to query the desired values via
SQL would be to write an extension which reads pg_controldata
(possibly as a backport of the above-mentioned functions).


Regards

Ian Barwick


-- 
  Ian Barwick                   http://www.2ndQuadrant.com/
  PostgreSQL Development, 24x7 Support, Training & Services