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 >>>> >> >>>> >> >>>> > >>>> >>> >>> >>
