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* Database system identifier from SQL
@ 2007-07-10 14:24 Peter Eisentraut <peter_e@gmx.net>
2007-07-10 15:23 ` Re: Database system identifier from SQL Tom Lane <tgl@sss.pgh.pa.us>
0 siblings, 1 reply; 4+ messages in thread
From: Peter Eisentraut @ 2007-07-10 14:24 UTC (permalink / raw)
To: pgsql-sql
Is there a way to query the database system identifier that pg_controldata
outputs from SQL?
--
Peter Eisentraut
http://developer.postgresql.org/~petere/
^ permalink raw reply [nested|flat] 4+ messages in thread
* Re: Database system identifier from SQL
2007-07-10 14:24 Database system identifier from SQL Peter Eisentraut <peter_e@gmx.net>
@ 2007-07-10 15:23 ` Tom Lane <tgl@sss.pgh.pa.us>
2007-07-10 18:06 ` Re: Database system identifier from SQL Peter Eisentraut <peter_e@gmx.net>
0 siblings, 1 reply; 4+ messages in thread
From: Tom Lane @ 2007-07-10 15:23 UTC (permalink / raw)
To: Peter Eisentraut <peter_e@gmx.net>; +Cc: pgsql-sql
Peter Eisentraut <peter_e@gmx.net> writes:
> Is there a way to query the database system identifier that pg_controldata
> outputs from SQL?
Don't think so. Do you have a use-case for providing a function to
return that?
regards, tom lane
^ permalink raw reply [nested|flat] 4+ messages in thread
* Re: Database system identifier from SQL
2007-07-10 14:24 Database system identifier from SQL Peter Eisentraut <peter_e@gmx.net>
2007-07-10 15:23 ` Re: Database system identifier from SQL Tom Lane <tgl@sss.pgh.pa.us>
@ 2007-07-10 18:06 ` Peter Eisentraut <peter_e@gmx.net>
2007-07-10 18:15 ` Re: Database system identifier from SQL Tom Lane <tgl@sss.pgh.pa.us>
0 siblings, 1 reply; 4+ messages in thread
From: Peter Eisentraut @ 2007-07-10 18:06 UTC (permalink / raw)
To: Tom Lane <tgl@sss.pgh.pa.us>; +Cc: pgsql-sql
Tom Lane wrote:
> Peter Eisentraut <peter_e@gmx.net> writes:
> > Is there a way to query the database system identifier that
> > pg_controldata outputs from SQL?
>
> Don't think so. Do you have a use-case for providing a function to
> return that?
I'd like to find out whether two connections are really to the same
server.
This is in the context of an installation routine for a database
application which pulls the connection parameters for several databases
from a configuration file and creates various things there. It should,
however, only create roles once if the connection parameters point to
the same server (if the user only expects a small installation, say).
A workaround is to compare inet_server_addr() and inet_server_port(),
but that is not 100% safe because it doesn't cover Unix-domain sockets
using different paths.
--
Peter Eisentraut
http://developer.postgresql.org/~petere/
^ permalink raw reply [nested|flat] 4+ messages in thread
* Re: Database system identifier from SQL
2007-07-10 14:24 Database system identifier from SQL Peter Eisentraut <peter_e@gmx.net>
2007-07-10 15:23 ` Re: Database system identifier from SQL Tom Lane <tgl@sss.pgh.pa.us>
2007-07-10 18:06 ` Re: Database system identifier from SQL Peter Eisentraut <peter_e@gmx.net>
@ 2007-07-10 18:15 ` Tom Lane <tgl@sss.pgh.pa.us>
0 siblings, 0 replies; 4+ messages in thread
From: Tom Lane @ 2007-07-10 18:15 UTC (permalink / raw)
To: Peter Eisentraut <peter_e@gmx.net>; +Cc: pgsql-sql
Peter Eisentraut <peter_e@gmx.net> writes:
> Tom Lane wrote:
>> Peter Eisentraut <peter_e@gmx.net> writes:
>>> Is there a way to query the database system identifier that
>>> pg_controldata outputs from SQL?
>>
>> Don't think so. Do you have a use-case for providing a function to
>> return that?
> I'd like to find out whether two connections are really to the same
> server.
Hmm. Seems a bit of an odd case, but on the other hand there might be
applications for it in connection with management of backups and
WAL-shipping and so forth. I have no objection to adding a function.
regards, tom lane
^ permalink raw reply [nested|flat] 4+ messages in thread
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2007-07-10 14:24 Database system identifier from SQL Peter Eisentraut <peter_e@gmx.net>
2007-07-10 15:23 ` Tom Lane <tgl@sss.pgh.pa.us>
2007-07-10 18:06 ` Peter Eisentraut <peter_e@gmx.net>
2007-07-10 18:15 ` Tom Lane <tgl@sss.pgh.pa.us>
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