cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Jeremy Sevellec <jeremy.sevel...@sarbacane.com>
Subject Re: No Transactions: An Example
Date Thu, 28 Jul 2011 07:37:49 GMT
Hi All,

Making transaction is my actual preoccupation of the moment.

My need is :

- update data in column family #1
- insert data in column family #2

My need is to see thes opérations in a single "transaction" because the
data is tightly coupled.

I use zookeeper/cage to make distributed lock to avoid multiple client
inserting or updating on the same data.

But there is a problem there is a fail when inserting in column family 2
because i have to "rollback" updated data of the column family #1.


My reading on the subject is that to solve the fail :
- Can we really consider that "write never fail" with cassandra from the
time the execution of a mutation happened on a node. What can be the
cause of fail at this point?
So is it important to thinking about this potential problem? (yes in my
opinion but i'm not totally sure).
- Make a retry first. Is there really a chance for the second try to
succeed if the first fail?
-  keep the "transaction data" to have the possibility to rollback
programmatically by deleting the inserting data. The problem is on the
updated data to rollback because old values are lost. I read what "Read
before write" is a bad idea to save old values before the update. the
problem remains, so how to do?


Do you have any feedback on this topic?

Regards,

Jérémy



Le jeudi 23 juin 2011 à 16:23 -0700, Les Hazlewood a écrit :

> Thanks for the pointer Ryan!
> 
> 
> 
> Regards,
> 
> 
> Les
> 
> 
> 
> 
> 


Mime
View raw message