It means Postgres can do a reliable backup (a consistent snapshot) of a
database without shutting down the database.
What you are asking for is replication, which is not easy to implement,
and almost damn impossible to get it RIGHT. (*curse at both Sybase and
Oracle replication servers*). (i.e. how do you resolve replication
conflicts, how do you resync databases for which you don't have
transaction logs, etc). I assume for Postgres, replication is a
possibility after WAL is implemented...
On Tue, 30 May 2000, Mihai Gheorghiu wrote:
> http://networkdna.com/database/index.html mentions that PostgreSQL is
> capable of "Online backup". What does that exactly mean?
> I'd like to be able to run a synchronization (in MS Access terms) (or
> "incremental backup"???), i.e. to have two databases in two locations,
> normally using only one of them and updating the other one. (Normal full
> backup looks unrealistic for 300MB over 1/3 of a T1.) In case the
> communication line between the two centers fails, users at the two ends
> should be able to use the local databases, and changes made during
> communication downtime be appended to the other database after communication
> resume.
