Is there update-in-place on maps?

2013-08-06 Thread Jan Algermissen
Hi, I think it does not fit the model of how C* does writes, but just to verify: Is there an update-in-place possibility on maps? That is, could I do an atomic increment on a value in a map? Jan

Re: Is there update-in-place on maps?

2013-08-06 Thread Alain RODRIGUEZ
Once again, this should answer your question : http://cassandra.apache.org/doc/cql3/CQL.html#collections Alain 2013/8/6 Jan Algermissen > Hi, > > I think it does not fit the model of how C* does writes, but just to > verify: > > Is there an update-in-place possibility on maps? That is, could I

Re: Is there update-in-place on maps?

2013-08-06 Thread Jan Algermissen
Alain, On 06.08.2013, at 11:17, Alain RODRIGUEZ wrote: > Once again, this should answer your question : > http://cassandra.apache.org/doc/cql3/CQL.html#collections yup, I understand the hint :-) However, since I am about to base application architecture on these capabilities, I wanted to make

Re: Is there update-in-place on maps?

2013-08-06 Thread Andy Twigg
Store pointers to counters as map values?

Re: Is there update-in-place on maps?

2013-08-06 Thread Jan Algermissen
On 06.08.2013, at 11:36, Andy Twigg wrote: > Store pointers to counters as map values? Sorry, but this fits into nothing I know about C* so far - can you explain? Jan

Re: Is there update-in-place on maps?

2013-08-06 Thread Andy Twigg
Counters can be atomically incremented ( http://wiki.apache.org/cassandra/Counters). Pick a UUID for the counter, and use that: c=map.get(k); c.incr() On 6 August 2013 11:01, Jan Algermissen wrote: > > On 06.08.2013, at 11:36, Andy Twigg wrote: > > > Store pointers to counters as map values? >

Re: Is there update-in-place on maps?

2013-08-07 Thread Aaron Morton
> As for the atomic increment, I take the answer is 'no, there is no atomic > increment, I have to pull the value to the client and send an update with the > new value'. Saying "atomic increment" is probably confusing. You cannot have Counters, the thing most people would think about when you sa

Re: Is there update-in-place on maps?

2013-08-07 Thread Alex Popescu
On Wed, Aug 7, 2013 at 10:47 AM, Aaron Morton wrote: > As for the atomic increment, I take the answer is 'no, there is no atomic > increment, I have to pull the value to the client and send an update with > the new value'. > > Saying "atomic increment" is probably confusing. > You cannot have Coun