On Fri, Jul 18, 2008 at 03:04:08PM +0200, Markus Schiltknecht wrote: > Hello Chris, > > chris wrote: >> Slony-I does the same, with the "variation" that it permits the >> option of using a "candidate primary key," namely an index that is >> unique+NOT NULL. >> >> If it is possible to support that broader notion, that might make >> addition of these sorts of logic more widely useful. > > Well, yeah, that's technically not much different, so it would > probably be very easy to extend Postgres-R to work on any arbitrary > Index. > > But what do we have primary keys for, in the first place? Isn't it > exactly the *primay* key into the table, which you want to use for > replication? Or do we need an additional per-table configuration > option for that? A REPLICATION KEY besides the PRIMARY KEY?
We have them because people are used to thinking in terms of a "PRIMARY KEY," not because that concept is actually distinguishable from a non-partial UNIQUE NOT NULL constraint. While I'm a "chicken" rather than a "pig" on this project <http://en.wikipedia.org/wiki/The_Chicken_and_the_Pig>, I believe that covering the more general case right from the start would be a much better plan. Cheers, David. -- David Fetter <[EMAIL PROTECTED]> http://fetter.org/ Phone: +1 415 235 3778 AIM: dfetter666 Yahoo!: dfetter Skype: davidfetter XMPP: [EMAIL PROTECTED] Remember to vote! Consider donating to Postgres: http://www.postgresql.org/about/donate -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
