Thanks Jonathan, I was only asking about the event listeners because an alternative we are considering is TIBCO Active Spaces which draws quite a lot of parallels to Cassandra.
I guess it would be interesting to find out how other people use Cassandra, i.e., is it your one stop shop for data storage or do you also store to a RDBMs to re-use the data? One factor I need to consider is our Business Intelligence platform that will need to use the data stored for reporting purposes. We are looking at using Cassandra for our real-time layer for Active-Active data centre use and perhaps have Oracle installed alongside for non-real-time use such that data is mediated to the Oracle database for other uses. Anthony From: Jonathan Shook [mailto:jsh...@gmail.com] Sent: Wednesday, 16 June 2010 10:58 AM To: user@cassandra.apache.org Subject: Re: Some questions about using Cassandra Doh! Replace "of" with "if" in the top line. On Tue, Jun 15, 2010 at 7:57 PM, Jonathan Shook <jsh...@gmail.com> wrote: There is JSON import and export, of you want a form of external backup. No, you can't hook event subscribers into the storage engine. You can modify it to do this, however. It may not be trivial. An easier way to do this would be to have a boundary system (or dedicated thread, for example) consume data in small amounts, using some temporal criterion, with a checkpoint. If the results of consuming the data are idempotent, you don't have to use a checkpoint, necessarily, but some cyclic rework may occur. If your storage layout includes temporal names, it should be straightforward. The details how exactly how would depend on your storage layout, but it is not unusual as far as requirements go. On Tue, Jun 15, 2010 at 7:49 PM, Anthony Ikeda < anthony.ik...@cardlink.com.au> wrote: We are currently looking at a distributed database option and so far Cassandra ticks all the boxes. However, I still have some questions. Is there any need for archiving of Cassandra and what backup options are available? As it is a no-data-loss system I'm guessing archiving is not exactly relevant. Is there any concept of Listeners such that when data is added to Cassandra we can fire off another process to do something with that data? E.g. create a copy in a secondary database for Business Intelligence reports? Send the data to an LDAP server? Anthony Ikeda Java Analyst/Programmer Cardlink Services Limited Level 4, 3 Rider Boulevard Rhodes NSW 2138 Web: www.cardlink.com.au | Tel: + 61 2 9646 9221 | Fax: + 61 2 9646 9283 ********************************************************************** This e-mail message and any attachments are intended only for the use of the addressee(s) named above and may contain information that is privileged and confidential. If you are not the intended recipient, any display, dissemination, distribution, or copying is strictly prohibited. If you believe you have received this e-mail message in error, please immediately notify the sender by replying to this e-mail message or by telephone to (02) 9646 9222. Please delete the email and any attachments and do not retain the email or any attachments in any form. ********************************************************************** _____________________________________________________________________ This e-mail has been scanned for viruses by MCI's Internet Managed Scanning Services - powered by MessageLabs. For further information visit http://www.mci.com ********************************************************************** This e-mail message and any attachments are intended only for the use of the addressee(s) named above and may contain information that is privileged and confidential. If you are not the intended recipient, any display, dissemination, distribution, or copying is strictly prohibited. If you believe you have received this e-mail message in error, please immediately notify the sender by replying to this e-mail message or by telephone to (02) 9646 9222. Please delete the email and any attachments and do not retain the email or any attachments in any form. **********************************************************************
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