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
