Re: No Transactions: An Example

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 t

Re: No Transactions: An Example

On 6/22/2011 9:18 AM, Trevor Smith wrote: Right -- that's the part that I am more interested in fleshing out in this post. Here is one way. Use MVCC . A single global clean-up process would be acceptable since it's not a sin

Re: No Transactions: An Example

On 6/23/2011 7:37 AM, Trevor Smith wrote: AJ, Thanks for your input. I don't fully follow though how this would work with a bank scenario. Could you explain in more detail? Thanks. Trevor I don't know yet. I'll be researching that. My working procedure is to figure out a way to handle e

Re: No Transactions: An Example

Thanks for the pointer Ryan! Regards, Les

Re: No Transactions: An Example

On Thu, Jun 23, 2011 at 2:05 PM, Les Hazlewood wrote: > Hi Dominic, > Thanks so much for providing this information.  I was unaware of Cages and > this looks like it could be used effectively for certain things. > >> This is because Cassandra uses the timestamps of columns that have been >> writte

Re: No Transactions: An Example

Hi Dominic, Thanks so much for providing this information. I was unaware of Cages and this looks like it could be used effectively for certain things. This is because Cassandra uses the timestamps of columns that have been > written during reconciliation to determine which should be persisted wh

Re: No Transactions: An Example

AJ, Thanks for your input. I don't fully follow though how this would work with a bank scenario. Could you explain in more detail? Thanks. Trevor On Wed, Jun 22, 2011 at 6:34 PM, AJ wrote: > I think Sasha's idea is worth studying more. Here is a supporting read > referenced in the O'Reilly C

Re: No Transactions: An Example

Domonic, Thank you for your answer. I enjoy how in your day to day work you are concerned with "who has the monster". It must be a fun to read your productions logs ("User[Shelly] received vampire"). I looked into Cages and this does seem interesting. I need to do more reading to have a better ta

Re: No Transactions: An Example

AJ this approach doesn't work if you need synchronized access to a value to prevent, for example, the lost update problem. Unless you synchronize access to something like bank balance transfers, you will quickly destroy your data On 22 June 2011 23:34, AJ wrote: > I think Sasha's idea is worth s

Re: No Transactions: An Example

I think Sasha's idea is worth studying more. Here is a supporting read referenced in the O'Reilly Cassandra book that talks about alternatives to 2-phase commit and synchronous transactions: http://www.eaipatterns.com/ramblings/18_starbucks.html If it can be done without locks and the busines

Re: No Transactions: An Example

Hi Trevor, I hope to post on my practical experiences in this area soon - we rely heavily on complex serialized operations in FightMyMonster.com. Probably the most simple serialized operation we do is updating nugget balances when, for example, there has been a trade of monsters. Currently we use

Re: No Transactions: An Example

Right -- that's the part that I am more interested in fleshing out in this post. Must one have background jobs checking the integrity of all transactions at some time interval? This gets hairy pretty quick with bank transactions (one unrolled transaction could cause many others to become unrolled.

Re: No Transactions: An Example

I would still maintain a record of the transaction ... so that I can do analysis post to determine if/when problems occurred ... On Wed, Jun 22, 2011 at 4:31 PM, Trevor Smith wrote: > Sasha, > How would you deal with a transfer between accounts in which only one half > of the operation was succes

Re: No Transactions: An Example

Sasha, How would you deal with a transfer between accounts in which only one half of the operation was successfully completed? Thank you. Trevor On Wed, Jun 22, 2011 at 10:23 AM, Sasha Dolgy wrote: > I'd implement the concept of a bank account using counters in a > counter column family. one

Re: No Transactions: An Example

I'd implement the concept of a bank account using counters in a counter column family. one row per account ... each column for transaction data and one column for the actual balance. just so long as you use whole numbers ... no one needs pennies anymore. -sd On Wed, Jun 22, 2011 at 4:18 PM, Trevo

No Transactions: An Example

Hello, I was wondering if anyone had architecture thoughts of creating a simple bank account program that does not use transactions. I think creating an example project like this would be a good thing to have for a lot of the discussions that pop up about transactions and Cassandra (and non-transa