pg_init

On Tue, Oct 08, 2019 at 10:03:03PM +0530, Natarajan R wrote:

I want to read pg_database from pg_init...

Is using heap_open() is possible? or else any other way is there ?

This is way too vague question - I have no idea what you mean by
pg_init, for example. And it's probably a good idea to explain what
you're trying to achieve.

regards

--
Tomas Vondra http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services

Tomas Vondra <tomas.vondra@2ndquadrant.com> wrote:

On Tue, Oct 08, 2019 at 10:03:03PM +0530, Natarajan R wrote:

I want to read pg_database from pg_init...

Is using heap_open() is possible? or else any other way is there ?

This is way too vague question - I have no idea what you mean by
pg_init, for example. And it's probably a good idea to explain what
you're trying to achieve.

This question was familiar to me so I searched the archives. It seems related
to

/messages/by-id/17058.1570166272@sss.pgh.pa.us

--
Antonin Houska
Web: https://www.cybertec-postgresql.com

On Wed, 9 Oct 2019 at 00:33, Natarajan R <nataraj3098@gmail.com> wrote:

I want to read pg_database from pg_init...

Is using heap_open() is possible? or else any other way is there ?

It's not possible from _PG_init .

I replied to a similar thread with details on how bgworkers can access
different databases; look at the archives.

The gist is that you have to register a bgworker that attaches to shared
memory and to a database (or use InvalidOid if you only want shared catalog
access), then do your work from there.

--
Craig Ringer http://www.2ndQuadrant.com/
2ndQuadrant - PostgreSQL Solutions for the Enterprise