Re: atomicity of a row write

On Mon, Jan 23, 2012 at 9:20 PM, Guy Incognito wrote: > hi all, > > having read: http://wiki.apache.org/cassandra/FAQ#batch_mutate_atomic > > i would like some clarification: > > is a write to a single row key in a single column family atomic in the sense > that i can do a batch mutate where i > >

Re: Atomicity Strategies

Thanks Aaron! On 6/22/2011 5:25 PM, aaron morton wrote: Atomic on a single machine yes. - Aaron Morton Freelance Cassandra Developer @aaronmorton http://www.thelastpickle.com On 23 Jun 2011, at 09:42, AJ wrote: On 4/9/2011 7:52 PM, aaron morton wrote: My understanding of wha

Re: Atomicity Strategies

Atomic on a single machine yes. - Aaron Morton Freelance Cassandra Developer @aaronmorton http://www.thelastpickle.com On 23 Jun 2011, at 09:42, AJ wrote: > On 4/9/2011 7:52 PM, aaron morton wrote: >> My understanding of what they did with locking (based on the examples) was >>

Re: Atomicity Strategies

On 4/9/2011 7:52 PM, aaron morton wrote: My understanding of what they did with locking (based on the examples) was to achieve a level of transaction isolation http://en.wikipedia.org/wiki/Isolation_(database_systems) I think the

Re: Atomicity of batch updates

See http://wiki.apache.org/cassandra/FAQ#batch_mutate_atomic Cheers - Aaron Morton Freelance Cassandra Developer @aaronmorton http://www.thelastpickle.com On 16 Jun 2011, at 06:26, chovatia jaydeep wrote: > Cassandra write operation is atomic for all the columns/super columns fo

Re: Atomicity of batch updates

Cassandra write operation is atomic for all the columns/super columns for a given row key in Column Family. So in your case not all previous operations (assuming each operation was on separate key) will be reverted. Thank you, Jaydeep From: Artem Orobets To:

Re: Atomicity Strategies

A Strategy that should Cover at least some use Cases is roughly like this: Given cf A and B should Be in Sync In write 'a' to cf A Add another Column 'Synchronisation_token' and Write a tuuid 'T' (or a timestamp or some Otter Value that Allows (Time based) ordering) As its value. On the related

Re: Atomicity Strategies

My understanding of what they did with locking (based on the examples) was to achieve a level of transaction isolation http://en.wikipedia.org/wiki/Isolation_(database_systems) I think the issue here is more about atomicity http://wiki.apache.org/cassandra/FAQ#batch_mutate_atomic We cannot g

Re: Atomicity Strategies

Here's a good writeup on how fightmymonster.com does it... http://ria101.wordpress.com/category/nosql-databases/locking/ -- Dan Washusen Make big files fly visit digitalpigeon.com On Saturday, 9 April 2011 at 11:53 AM, Alex Araujo wrote: On 4/8/11 5:46 PM, Drew Kutcharian wrote: > > I'm interes

Re: Atomicity Strategies

On 4/8/11 5:46 PM, Drew Kutcharian wrote: I'm interested in this too, but I don't think this can be done with Cassandra alone. Cassandra doesn't support transactions. I think hector can retry operations, but I'm not sure about the atomicity of the whole thing. On Apr 8, 2011, at 1:26 PM, Ale

Re: Atomicity Strategies

I'm interested in this too, but I don't think this can be done with Cassandra alone. Cassandra doesn't support transactions. I think hector can retry operations, but I'm not sure about the atomicity of the whole thing. On Apr 8, 2011, at 1:26 PM, Alex Araujo wrote: > Hi, I was wondering if th

Re: atomicity in cassandra

There is no undo or redo log in Cassandra. From Cassandra perspective if the operation gets logged in commit log, it is considered committed. Remember the eventual consistency... On Mon, Mar 28, 2011 at 6:21 PM, Saurabh Sehgal wrote: > I have seen this question pop up once or twice in mailing

Re: atomicity

ache.org > Sent: Mon, 20 December, 2010 12:05:17 AM > Subject: Re: atomicity > >> Say I have two processes on separate machines, and a Cassandra cluster over >> several machines. If the first process writes (insert) to a column while the >> second process reads (get

Re: atomicity

Thanks a lot, Peter. K. - Original Message From: Peter Schuller To: user@cassandra.apache.org Sent: Mon, 20 December, 2010 12:05:17 AM Subject: Re: atomicity > Say I have two processes on separate machines, and a Cassandra cluster over > several machines. If the first process

Re: atomicity

> Say I have two processes on separate machines, and a Cassandra cluster over > several machines. If the first process writes (insert) to a column while the > second process reads (get / get_slice / get_range_slices / others?) from that > column (say the consistency level is QUORUM if that makes a

Re: atomicity

On Sat, Dec 18, 2010 at 11:02 PM, Kevin Irwig wrote: > Hi, > > Say I have two processes on separate machines, and a Cassandra cluster over > several machines. If the first process writes (insert) to a column while > the > second process reads (get / get_slice / get_range_slices / others?) from >