On Tue, May 15, 2012 at 3:16 PM, Mike Christensen <mike@kitchenpc.com> wrote:
>>> I've never done that in PG before, but I've used named connections
>>> with Oracle. Is it the same sort of deal? There's a file on the disk
>>> somewhere with the connection info? Either way, I'm sure it's a RTFM
>>> thing so I'll look into it.
>>
>> yeah, there's a good example in the docs here:
>> http://www.postgresql.org/docs/9.1/static/contrib-dblink-connect.html
>>
>> btw, if you have a structure in test that matches production, then you
>> can use a composite type trick to avoid having to specify fields as
>> long as you keep those structures in sync (which you have to do
>> anyways). try:
>>
>> select (u).* from dblink(
>> 'hostaddr=123.123.123.123 dbname=ProductionDB user=ROUser
>> password=secret',
>> 'select u from users u') as t1(u users);
>>
>> it should work as long as users exists on both sides and has exactly
>> the same structure. using that method it's trivial to make a dblink
>> wrapper that could query any table but you couldn't wrap it into a
>> single view obviously.
>
> Ah ok, now I'm following.. Yea, I had read up on the dblink_connect()
> function, however it seemed like an extra step to have to open this
> connection every time. It would avoid duplicating the connection info
> across multiple views though. What I was hoping for was the ability
> to store this information somewhere. Doesn't PG allow custom
> variables for sessions, users, and databases? Or is this something
> that could be stored in pg_*.conf or as an environment variable?
yes, they are called 'tables' :-). stick your connection string in a
table somewhere and do:
create view v as
select (u).* from dblink((select connstr from yadda where yadda), ...);
merlin
