Re: Federated Postgresql architecture ?

On Thu, Jun 26, 2008 at 4:33 PM, kevin kempter
<kevin(at)kevinkempterllc(dot)com> wrote:
> Anyone have any experiences to share per setting up a federated architecture
> with PostgreSQL ? I wonder if the dblink contrib works well in a federated
> scenario, specifically in the setup of the federated views which equate to a
> select * from the same table on each federated server ?

Because Postgres currently lacks the ability to push down predicates
to individual nodes over a database link, you have to spend a good
amount of time writing PL set-returning functions capable of adding
appropriate WHERE clauses to queries sent over the link. There are
other things you can do, but it's mostly hackery at this point in
time. IIRC, David Fetter is trying to get some of the required
predicate information exposed for use in DBI-Link.

Not to self-plug, but if you require it, EnterpriseDB includes
Oracle-style database links (SELECT col FROM table(at)node) which support
predicate push-down.

--
Jonah H. Harris, Sr. Software Architect | phone: 732.331.1324
EnterpriseDB Corporation | fax: 732.331.1301
499 Thornall Street, 2nd Floor | jonah(dot)harris(at)enterprisedb(dot)com
Edison, NJ 08837 | http://www.enterprisedb.com/