Thanks for your help everyone. Sylvain, as I understand it, the scenario I described above is not resolved by CASSANDRA-6561, correct?
(This scenario may not matter to most folks, which is totally fine, I just want to make sure that I understand.) Should I instead look into using the Thrift API to address this? Best regards, Clint On Tue, Feb 25, 2014 at 11:30 PM, Sylvain Lebresne <sylv...@datastax.com>wrote: > Sorry to interfere again here but CASSANDRA-5633 will not be picked up > because pretty much everything it was set to fix is fixed by > CASSANDRA-6561, this is *not* a syntax problem anymore. > > > On Wed, Feb 26, 2014 at 3:18 AM, Tupshin Harper <tups...@tupshin.com>wrote: > >> Unfortunately there is no option to vote for a "resolved" ticket, but if >> you can propose a better syntax that people agree on, you could probably >> get some fresh traction on it. >> >> -Tupshin >> On Feb 25, 2014 7:20 PM, "Clint Kelly" <clint.ke...@gmail.com> wrote: >> >>> Hi Tupshin, >>> >>> Thanks for your help! Unfortunately in my case, I will need to do a >>> compare and set in which the compare is against a value in a dynamic column. >>> >>> In general, I need to be able to do the following: >>> >>> - Check whether a given value exists in a dynamic column >>> - If so, perform some number of insertions / deletions for dynamic >>> columns in the same row (i.e., with the same partition key as the dynamic >>> column used for the compare) >>> >>> I think you are correct that I need >>> https://issues.apache.org/jira/browse/CASSANDRA-5633 to be >>> implemented. Is there any way to vote for that to get picked up again? :) >>> >>> Best regards, >>> Clint >>> >>> >>> >>> >>> >>> On Mon, Feb 24, 2014 at 2:32 PM, Tupshin Harper <tups...@tupshin.com>wrote: >>> >>>> Hi Clint, >>>> >>>> That does appear to be an omission in CQL3. It would be possible to >>>> simulate it by doing >>>> BEGIN BATCH >>>> UPDATE foo SET z = 10 WHERE x = 'a' AND y = 1 IF t= 2 AND z=10; >>>> UPDATE foo SET t = 5,z=6 where x = 'a' AND y = 4 >>>> APPLY BATCH; >>>> >>>> However, this does a redundant write to the first row if the condition >>>> holds, and I certainly wouldn't recommend doing that routinely. >>>> >>>> Alternatively, depending on your needs, you might be able to use a >>>> static column (coming with 2.0.6) as your conditional flag, as that column >>>> is shared by all rows in the partition. >>>> >>>> -Tupshin >>>> >>>> >>>> >>>> On Mon, Feb 24, 2014 at 3:57 PM, Clint Kelly <clint.ke...@gmail.com>wrote: >>>> >>>>> Hi Tupshin, >>>>> >>>>> Thanks for your help; I appreciate it. >>>>> >>>>> Could I do something like the following? >>>>> >>>>> Given the same table you started with: >>>>> >>>>> x | y | t | z >>>>> ---+---+---+---- >>>>> a | 1 | 2 | 10 >>>>> a | 2 | 2 | 20 >>>>> >>>>> I'd like to write a compare-and-set that does something like: >>>>> >>>>> "If there is a row with (x,y,t,z) = (a,1,2,10), then update/insert a >>>>> row with (x,y,t,z) = (a,3,4,5) and update/insert a row with (x,y,t,z) >>>>> = (a,4,5,6)." >>>>> >>>>> >>>>> I don't see how I could do this with what you outlined above---just >>>>> curious. It seems like what I describe above under the hood would be >>>>> a compare-and-(batch)-set on a single wide row, so it maybe is >>>>> possible with the Thrift API (I have to check). >>>>> >>>>> Thanks again! >>>>> >>>>> Best regards, >>>>> Clint >>>>> >>>>> On Sat, Feb 22, 2014 at 11:38 AM, Tupshin Harper <tups...@tupshin.com> >>>>> wrote: >>>>> > #5633 was actually closed because the static columns feature >>>>> > (https://issues.apache.org/jira/browse/CASSANDRA-6561) which has >>>>> been >>>>> > checked in to the 2.0 branch but is not yet part of a release (it >>>>> will be in >>>>> > 2.0.6). >>>>> > >>>>> > That feature will let you update multiple rows within a single >>>>> partition by >>>>> > doing a CAS write based on a static column shared by all rows within >>>>> the >>>>> > partition. >>>>> > >>>>> > Example extracted from the ticket: >>>>> > CREATE TABLE foo ( >>>>> > x text, >>>>> > y bigint, >>>>> > t bigint static, >>>>> > z bigint, >>>>> > PRIMARY KEY (x, y) ); >>>>> > >>>>> > insert into foo (x,y,t, z) values ('a', 1, 1, 10); >>>>> > insert into foo (x,y,t, z) values ('a', 2, 2, 20); >>>>> > >>>>> > select * from foo; >>>>> > >>>>> > x | y | t | z >>>>> > ---+---+---+---- >>>>> > a | 1 | 2 | 10 >>>>> > a | 2 | 2 | 20 >>>>> > (Note that both values of "t" are 2 because it is static) >>>>> > >>>>> > >>>>> > begin batch update foo set z = 1 where x = 'a' and y = 1; update >>>>> foo set z >>>>> > = 2 where x = 'a' and y = 2 if t = 4; apply batch; >>>>> > >>>>> > [applied] | x | y | t >>>>> > -----------+---+------+--- >>>>> > False | a | null | 2 >>>>> > >>>>> > (Both updates failed to apply because there was an unmet conditional >>>>> on one >>>>> > of them) >>>>> > >>>>> > select * from foo; >>>>> > >>>>> > x | y | t | z >>>>> > ---+---+---+---- >>>>> > a | 1 | 2 | 10 >>>>> > a | 2 | 2 | 20 >>>>> > >>>>> > >>>>> > begin batch update foo set z = 1 where x = 'a' and y = 1; update foo >>>>> set z = >>>>> > 2 where x = 'a' and y = 2 if t = 2; apply batch; >>>>> > >>>>> > [applied] >>>>> > ----------- >>>>> > True >>>>> > >>>>> > (both updates succeeded because the check on t succeeded) >>>>> > >>>>> > select * from foo; >>>>> > x | y | t | z >>>>> > ---+---+---+--- >>>>> > a | 1 | 2 | 1 >>>>> > a | 2 | 2 | 2 >>>>> > >>>>> > Hope this helps. >>>>> > >>>>> > -Tupshin >>>>> > >>>>> > >>>>> > >>>>> > On Fri, Feb 21, 2014 at 6:05 PM, DuyHai Doan <doanduy...@gmail.com> >>>>> wrote: >>>>> >> >>>>> >> Hello Clint >>>>> >> >>>>> >> The Resolution status of the JIRA is set to "Later", probably the >>>>> >> implementation is not done yet. The JIRA was opened to discuss >>>>> about impl >>>>> >> strategy but nothing has been coded so far I guess. >>>>> >> >>>>> >> >>>>> >> >>>>> >> On Sat, Feb 22, 2014 at 12:02 AM, Clint Kelly < >>>>> clint.ke...@gmail.com> >>>>> >> wrote: >>>>> >>> >>>>> >>> Folks, >>>>> >>> >>>>> >>> Does anyone know how I can modify multiple rows at once in a >>>>> >>> lightweight transaction in CQL3? >>>>> >>> >>>>> >>> I saw the following ticket: >>>>> >>> >>>>> >>> https://issues.apache.org/jira/browse/CASSANDRA-5633 >>>>> >>> >>>>> >>> but it was not obvious to me from the comments how (or whether) >>>>> this >>>>> >>> got resolved. I also couldn't find anything in the DataStax >>>>> >>> documentation about how to perform these operations. >>>>> >>> >>>>> >>> I'm in particular interested in how to perform a compare-and-set >>>>> >>> operation that modifies multiple rows (with the same partition key) >>>>> >>> using the DataStax Java driver. >>>>> >>> >>>>> >>> Thanks! >>>>> >>> >>>>> >>> Best regards, >>>>> >>> Clint >>>>> >> >>>>> >> >>>>> > >>>>> >>>> >>>> >>> >
