Re: Per-server univocal identifier

"Giampaolo Tomassoni" <g(dot)tomassoni(at)libero(dot)it> writes:
> I'm looking for a way to univocally identify the server on which a sql function or statement is running. My idea would be something close to the value returned by a 'host -f' under linux: the FQDN of the host, but even a serial code or a number would be fine to me. It needs only to be immutable, I guess.

Perhaps inet_server_addr() and inet_server_port() would answer. These
aren't super-useful on local connections, however.

How "immutable" do you want it to be exactly? The system_identifier
embedded in pg_control might be interesting if you want something that
will change at initdb. I don't think there's a way to look at that from
SQL but you could write a C function to access it.

regards, tom lane