C-JDBC 1.0 Released

StupidEngineer writes "The C-JDBC is a middleware RAID system for databases written in Java. The 1.0 release is finally ready for download after years of the team's hard work. The system definitely has come a long way and is probably a very viable solution for those of us that can't afford large DB clustering solutions, yet still want good scalability and redundancy."

cloudscape

[raffe]

Will it work with the asf cloudescape db?

Anything with a JDBC driver

[JavaRob]

More details in my post below, but yes -- basically any RDBMS with a JDBC driver is suddenly fair game for clustering. You can even have heterogeneous databases in your cluster!

Cool stuff.

Nonsense... this is an awesome project

[JavaRob]

Um... this isn't a database engine (though there *are* database engines written in Java). And I think you're still thinking of Java applets, which is really not a strong point. I'll skip the rant in favor of providing some actual info on the project, though, since it looks really cool.

Here's the homepage [objectweb.org], with much better info that the download link above.

Basically, they provide a standard JDBC interface that your application can use normally (no code modification needed at all!). The driver forwards t

Re:Nonsense... this is an awesome project

[StupidEngineer]

Oops, sorry, yeah. :) My bad, grammar bad. :) Missed a comma.

Fantastic!

[Anonymous Coward]

This is an excellent idea: write a JDBC driver that talks to other JDBC drivers to make your application think you have only one database server, all the while this funky meta-driver does load balancing and replication, thus automatically augmenting your application's database availability and performance. Cool!

Memcached

[captainclever]

This looks like a very cool project.

For all those people reading this thread looking for a cheap way to resolve DB load problems for websites etc, check out Memcached:

http://www.danga.com/memcached/

After adding a memcache layer to your site you might find 1 lowly database server is more than enough ;)

ha-jdbc

[StupidEngineer]

BTW, has anyone checked out the HA-JDBC project? http://ha-jdbc.sourceforge.net/

It's not as feature rich as c-jdbc, but it might be another alternative for us that avoid the expensive clustering systems. /still feels stupid about incorrectly submitting the news item.

How about transactions?

[TheSunborn]

I looks very intelesting, but I searched the documentation and could not find any mention of transactions. How do they handle that?

I mean how do they handle locking with things such as SELECT FOR UPDATE?
I mean if to clients different SELECT FOR UPDATE fon the same row, could you not have a situation where one client have the lock on db1 and an other client have the lock on db2 for the same row?.

And how do they handle transaction order. I mean if to transactions a and b are comitted at the same time, could

Re:How about transactions?

[JavaRob]

The docs [objectweb.org] (try the user guide) do mention transactions, but I didn't see any detailed discussion of how they handle it....

Honestly, you *might* have to wait until all databases were finished, when performing an update, insert or delete. Otherwise how could it possibly handle a rollback (which the docs do mention, so they're supported)?

This isn't as bad as it sounds, though. It's not as if the databases were updated in sequence; they're all updating at once, so it won't take any longer than if you were us

Re:How about transactions?

[atallah]

You obviously are trying to be flamebait, but in addition you are severely confused - J2EE Container Managed Transactions are extremely effective, going beyond simple database transactions and extending to application transactions, where several different types of entities can be rolled back (e.g. Message Queues) in addition to database transactions.

Nice project

[jfsather]

It is nice to see a project like this. Kind of odd since I was just asked to look into how to do this. It would be helpful if you had to use Tomcat, but most of the paid for servers already have something like this (e.g. MultiPools in WebLogic).

Of course it would be useless if you couldn't cluster the C-JDBC server as well--the reason you are using multiple DBs is to not have a single point of failure.

Now what I have to figure out is syncing all the databases--that would be quite a few triggers that nee

Re:Nice project

[jfsather]

Okay, I RTFDocs and figured out what it is doing. Selects are balanced and anything else is broadcast (including stored procs). Not a bad way to do it, but then you would need to be very aware of response times from each DB since on an update/insert it would seem that it would take as long as the slowest responding DB. No real way around that, I'm guessing. It is probably best with multiple instances of the same DB type rather than the mix-type they show in the docs, however. All of this, of course, as