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PostgreSQL Inc. Open Sources Replication Solution
Martin Marvinski writes "PostgreSQL Inc, the commercial company providing replication software and support for PostgreSQL, open sourced their eRServer replication product. This makes PostgreSQL one step closer to being able to replace Oracle as the de facto RDBMS standard. More information can be found on PostgreSQL's website."
There is an enormous distance between "viable alternative" and "defacto standard" and the path between them is not paved with features.
Check monster.com. More companies look for people with mySQL experiences. Check the book stores. You will see more books about mySQL. Even though PostgreSQL has more features and is more promising and powerful, mySQL gets more publicity. This means that mySQL will be the open source database that will replace most commercial databases. It's sad but true.
Ever heard of InnoDB? MySQL lets you choose -- on a table-by-table basis -- exactly what parts of your application need to support transactions, foreign keys, etc.
Odd, neither Slashdot nor Yahoo! Finance seem to be having corruption problems...
Adding extra memory, CPUs, or slave servers obviously has no impact on server performance. (Yes, replication is... clumsy, at best, but depending on the application, it can work quite well.)
Compared to Postgres?
You would still have to pay boatloads for support...even with postgres... Open Source does not mean 24/7 Support calls...
Implementing replication at the application layer is about as much fun as implementing table locking at that layer.
I can't say a bad thing about postgresql; this was really the only thing I felt the need for. For anyone who hasn't tried it you really should. Although I don't want to start a MySQL v postgresql flamewar, after trying both I think that postgres has the edge. Mysql was undisputably easier to work with and (at the time) was faster. PostgreSQL has moved on at a much faster rate though. In particular postgresql has solid support for transactions, large objects, subselects, object oriented tables. I'm convinced that if you use databases long enough you'll want every last one of these and won't be able to do without.
Carpe Daemon
This is indeed good news, as free software always is. But eRServer can only operate in single-master mode, which makes it unsuitable for high-availability kind of work. Single-master systems are good for load-balancing on installations where most of the queries to the DB are SELECTs.
eRServer comes a bit late. We already have PostgreSQL Replicator, which is multi-master. Unfortunately PG Replicator is not supported anymore. The latest version it can work with is 7.1, and the project's latest news are timestamped nearly two years ago.
While this is a nice step forward, the real reason large sites utilize Oracle is because of synchronous replication.
The replication needs to be able to keep all data consistent across multiple servers, without any conflicts. Then, if a particular server goes down, the DNS can simply fail over to a second server.
Once the above has been achieved, then we have a viable alternative to Oracle.
> This makes PostgreSQL one step closer to being able to replace Oracle...
Please! While this may help win the hearts and minds of OOS geeks, it does little to improve their standing in the business world.
Oracle is as established in the database world as Microsoft is on the desktop. This alone would doom any OOS wannabe to quiet places like web server back ends where they already do well anyway ( e.g. mySql ).
Put aside the technical considerations, support, client base, etc and PostgreSQL still offers as much of a threat to Oracle as mySql or dBase. The only real threat I've seen to Oracle supremacy is Microsoft's SQL Server but, of course, that's only in MS shops.
Please let me know if I'm wrong...
I visited the site, and the commercial site too and it seems this is only simple replication with the master being a single point of failure. F.E.
1. update a row in the master
2. master replicates the update to multiple slaves
3. clients perform select operations against the slaves (nice load balancing opportunity)
4. the master crashes
5. No one can write until the master comes back online.
Here are the steps that seem to be missing:
6. the slaves elect a new master
7. if the old master comes back up it must realize a new master is present and become a slave.
8. clients using JDBC would need some mechanism of finding out what the new master is when an update/insert/delete fails.
Cheers.
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I like PostgreSQL, and Open Source deserves capitalization, but I'd like to hear an enterprise DBA's perspective on if this really compares to Oracle's configurability, clustering capabilities, or the seamless swapping of redundant database packages when deployed on, say, an EMC 1000, for reliability and failover. BTW, for this request, "enterprise" = Fortune 100, not Joe's Web Hosting.
Like the subject says, I'm not a DBA, but I know some pretty heavy-duty ones that say nothing beats Oracle running on HP Superdomes with EMC storage.
clearly the poster does not understand the intricacies of replication in a real-time environment.
you can not pull the data out of table and stuff it into another table under even a reasonable workload.
but i understand this is slashdot and technical relevance need not necessarily apply.
Even though the article is about an improvement in the PostgreSQL community, the comments are mostly pgsql vs mysql. People in the bazaar need to have personal motivations to work on opensource projects, mostly to have something against Microsoft, but increasingly, it is becoming a series of team wars. Linux vs BSD, then we had KDE vs GNOME and now qmail vs postfix and mysql vs pgsql. More than a decade ago we had vi vs emacs and BSD vs SYSV.
What the posters here need to realize is that it is exactly this competition that is driving the projects. If MySQL was not given the press and did not have its cult following, we would not see this pace of development for pgsql. The developments for FreeBSD really improved to compete with Linux although their developers claim they are not competing... they do have the fear Linux will supplant them.
What is interesting to note is that in most of these project wars, both projects really survive and get two different niches of their own. This was true of bash vs csh, BSD vs SYSV, BSD vs Linux, KDE vs GNOME, and now MySQL will become the standard entry level database and pgsql the higher level.
I use pgsql because my databases have complicated requirements that MySQL cannot meet. Yet MySQL is the quick and dirty solution when I have to set things up fast. For all new learners I always suggest MySQL. For people thinking of replacing or duplicating their ERP systems, I always suggest pgsql. I even know how to program in sleepycat's db and know where it should replace mysql in smaller embedded systems and where the mysql license cannot be used.
I believe this competition is coming to a close since pgsql has taken a big lead over MySQL in features, and therefore made itself more difficult to deal with especially for newbies. All I can say about the postgresql replication is bravo, and hope MySQL doesnt follow suit so it remains the simple fast and easy database in its own niche.
"Give orange me give eat orange me eat orange give me eat orange give me you." -Nim Chimpsky
No I don't work for MS, no I'm not in bed with thier marketing department, no I'm not afraid of the command line, etc. I just can't deny that it is a good product. In my opinion the best product MS has ever released, and much cheaper than Oracal.
Granted, I still don't trust MS to be secure, so I never let it be internet facing. To get around that you let the web server be internet facing and only allow connections to the db from that one box. They would have to comprimise you from the inside first, or take control of the web server. And there is nothing stopping you from using Linux and Apache on that web server. We do the same thing with Exchange. I don't like exchange nearly as much as I like MSSQL but the VP's demand it so we just put it behind the firewall and relay all the outbound mail to a Unix-based mailserver in the DMZ.
Unix security on the outside, MS useability on the inside.
Go ahead and flame me now, I'm ready for you.
Sigs are out of style, so I'm not going to use one...oh wait..