Mailing-List: contact user-help@cassandra.apache.org; run by ezmlm
Precedence: bulk
Reply-To: user@cassandra.apache.org
Received-SPF: pass (athena.apache.org: local policy)
DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws;
  s=s1024; d=yahoo.com;
  h=Message-ID:X-YMail-OSG:Received:X-Mailer:Date:From:Subject:To:MIME-Version:Content-Type;
  b=V6hA28dCLL6eoLJQp9KA4HSGEr2jDTV4bDp+vTWde/RbLQFOsgPK5PVjdYhk5OyXL8EaraGreHcA6ZcdfuGfF1+7+qxTQG0bKAgi4ihxnb+1Z0LhMvnsWrXaws+J1R+ywjsLXT3oVH3yRa+imwIMVME5aGknMAJJjqoKDnYmT84=;
Message-ID: <104658.41794.qm@web55201.mail.re4.yahoo.com>
Date: Tue, 7 Sep 2010 15:42:32 -0700 (PDT)
From: kannan chandrasekaran <ckannanck@yahoo.com>
Subject: Few questions regarding cassandra deployment on windows
To: user@cassandra.apache.org
MIME-Version: 1.0
Content-Type: multipart/alternative; boundary="0-1328242015-1283899352=:41794"

--0-1328242015-1283899352=:41794
Content-Type: text/plain; charset=us-ascii

Hi All,

We are currently considering Cassandra for our application. 

Platform:  
* a single-node cluster.
* windows '08
* 64-bit jvm  

For the sake of brevity let,
Cassandra service =  a single node cassandra server running as an embedded 
service inside a JVM


My use cases: 
1) Start with a schema ( keyspace and set of column families under it) in a 
cassandra service
2) Need to be able to replicate the same schema structure (add new 
keyspace/columnfamilies with different names ofcourse).
3) Because of some existing limitations in my application, I need to be able to 
write to the keyspace/column-families from a cassandra service and read the 
written changes from a different cassandra service. Both the write and the read 
"cassandra-services" are sharing the same Data directory. I understand that the 
application has to take care of any naming collisions. 


Couple Questions related to the above mentioned usecases:
1) I want to spawn a new JVM and launch Cassandra as an embedded service 
programatically instead of using the startup.bat. I would like to know if that 
is possible and any pointers in that direction would be really helpful. ( 
use-case1)
2) I understand that there are provisions for live schema changes in 0.7 ( thank 
you guys !!!), but since I cant use a beta version in production, I am 
restricted to 0.6 for now. Is it possible to to support use-case 2 in 0.6.5 ? 
More specifically, I am planning to make runtime changes to the storage.conf xml 
file followed by a cassandra service restart
3) Can I switch the data directory at run-time ?  (use-case 3). In order to not 
disrupt read while the writes are in progress, I am thinking something like, 
copy the existing data-dir into a new location; write to a new data directory; 
once the write is complete; switch pointers and restart the cassandra service to 
read from the new directory to pick up the updated changes

Any help is greatly appreciated.

Thanks 
Kannan


--0-1328242015-1283899352=:41794
Content-Type: text/html; charset=us-ascii

<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:arial,helvetica,sans-serif;font-size:12pt"><div>Hi All,<br><br>We are currently considering Cassandra for our application. <br><br>Platform:&nbsp; <br>* a single-node cluster.<br>* windows '08<br>* 64-bit jvm&nbsp; <br><br>For the sake of brevity let,<br>Cassandra service =&nbsp; a single node cassandra server running as an embedded service inside a JVM<br><br><br>My use cases: <br>1) Start with a schema ( keyspace and set of column families under it) in a cassandra service<br>2) Need to be able to replicate the same schema structure (add new keyspace/columnfamilies with different names ofcourse).<br>3) Because of some existing limitations in my application, I need to be able to write to the keyspace/column-families from a cassandra service and read the written changes from a different cassandra service. Both the write and the read
 "cassandra-services" are sharing the same Data directory. I understand that the application has to take care of any naming collisions. <br><br><br>Couple Questions related to the above mentioned usecases:<br>1) I want to spawn a new JVM and launch Cassandra as an embedded service programatically instead of using the startup.bat. I would like to know if that is possible and any pointers in that direction would be really helpful. ( use-case1)<br>2) I understand that there are provisions for live schema changes in 0.7 ( thank you guys !!!), but since I cant use a beta version in production, I am restricted to 0.6 for now. Is it possible to to support use-case 2 in 0.6.5 ? More specifically, I am planning to make runtime changes to the storage.conf xml file followed by a cassandra service restart<br>3) Can I switch the data directory at run-time ?&nbsp; (use-case 3). In order to not disrupt read while the writes are in progress, I am thinking something
 like, copy the existing data-dir into a new location; write to a new data directory; once the write is complete; switch pointers and restart the cassandra service to read from the new directory to pick up the updated changes<br><br>Any help is greatly appreciated.<br><br>Thanks <br>Kannan<br><br></div>
</div><br>

      </body></html>
--0-1328242015-1283899352=:41794--