On 2/6/07, Jim Nasby <decibel@decibel.org> wrote:
> On Feb 5, 2007, at 12:53 PM, Andrew Hammond wrote:
> > On Jan 26, 2:38 pm, t...@sss.pgh.pa.us (Tom Lane) wrote:
> >> Rick Gigger <r...@alpinenetworking.com> writes:
> >>> I thought that the following todo item just barely missed 8.2:
> >>> "Allow a warm standby system to also allow read-only statements
> >>> [pitr]
> >>
> >> No, it's a someday-wishlist item; the work involved is not small.
> >
> > Slony1 has supported log-shipping replication for about a year now. It
> > provides similar functionality.
>
> Not really....
>
> 1) It's not possible for a PITR 'slave' to fall behind to a state
> where it will never catch up, unless it's just on inadequate
> hardware. Same isn't true with slony.
I imagine that there are ways to screw up WAL shipping too, but there
are plenty more ways to mess up slony.
> 2) PITR handles DDL seamlessly
> 3) PITR is *much* simpler to configure and maintain
4) You need 3 databases to do log shipping using slony1. An origin, a
subscriber which generates the logs and obviously the log-replica.
All of which is why I qualified my statement with "similar".
