Re: PostgreSQL in the press again

Guys,

> > What are the other solutions?
>
> Mammoth Replicator, and whatever is happening with eRServer these
> days...

dbMirror is still quite popular.   This is partly because it is better suited
for "very slow replication", e.g. replication via FTP server once per day, a
la MusicBrainz.

Both pgPool and C-JDBC offer synchronous query distribution based MM
replication, although at the present time neither is transaction-safe.  When
we get XA, C-JDBC will become a very viable alternative.

The issue talking with the press is that you need to communicate to them that
"Replication" is a general programming topic, and NOT a single task, just
like "database" is.    Nobody in the industry would expect to use the same
database for all purposes; neither would anyone expect to use the same
replication tool for all purposes.   The reason you get this question all the
time is:
1) Many DBMSs (SQL Server, MySQL) support only one replication tool;
2) reporters have no clear idea what "replication" is.

Personally, I'd answer:

"Slony-I is undoubtedly our most popular replication tool.   It supports
Master-Slave High Availability Replication.   However, there are a number of
other solutions, such as dbMirror, eRServer, pgPool, C-JDBC, and the
proprietary Mammoth Replicator, all of which are in wide use because they
solve different replication problems than Slony-I does.  Replication is not a
single solution for a single problem; it is several solutions for a wide
array of different problems.  That's why no one replication tool will ever be
the "default" replication for PostgreSQL."

--
--Josh

Josh Berkus
Aglio Database Solutions
San Francisco