Perfect. Thanks. Let me see what I can cook up as a PoC.
The specific use case we are looking to address is for real-time aggregations, done in memory, then periodically flushed to C*. (e.g. every 30 seconds) (similar to what Druid does, but native on top of C*) In this scenario, we aggregate app-side for a specific time slice/partition of data. We want to update the aggregate value only if that time slice/partition has not already been incorporated into the value. If we have a native way to check to see if the partition was already incorporated as part of the conditional update, it will simplify the app layer. -brian --- Brian O'Neill Chief Technology Officer Health Market Science, a LexisNexis Company 215.588.6024 Mobile • @boneill42 <http://www.twitter.com/boneill42> This information transmitted in this email message is for the intended recipient only and may contain confidential and/or privileged material. If you received this email in error and are not the intended recipient, or the person responsible to deliver it to the intended recipient, please contact the sender at the email above and delete this email and any attachments and destroy any copies thereof. Any review, retransmission, dissemination, copying or other use of, or taking any action in reliance upon, this information by persons or entities other than the intended recipient is strictly prohibited. On 2/6/15, 9:50 AM, "Benedict Elliott Smith" <belliottsm...@datastax.com> wrote: >It's quite possible support could be added to evaluate a UDF as part of >the >condition check. The code you're looking for are implementors of >CASRequest.appliesTo(), in CQL3CasRequest and >CassandraServer.ThriftCASRequest > >It seems like https://issues.apache.org/jira/browse/CASSANDRA-8488 would >offer the basic functionality, except that it is expected to require ALLOW >FILTERING, which is unlikely to be permitted for a CAS operation, since >the >implication is that the work is too expensive for normal use. Such a >constraint is probably not necessary if a clustering prefix is provided, >though (i.e. a full CQL row key). > >On Fri, Feb 6, 2015 at 2:38 PM, Brian O'Neill <b...@alumni.brown.edu> >wrote: > >> >> All, >> >> I¹m just looking for a little directionŠ >> >> Anyone know where I can find the code that checks the condition in a >> conditional update? >> We¹d love to have more expressive conditions, beyond just equality. >>(e.g. >> column contains? value) >> >> I wanted to see how hard this would be to contribute. >> Is such a JIRA already open? >> >> -brian >> >> --- >> Brian O'Neill >> Chief Technology Officer >> Health Market Science, a LexisNexis Company >> 215.588.6024 Mobile € @boneill42 <http://www.twitter.com/boneill42> >> >> >> This information transmitted in this email message is for the intended >> recipient only and may contain confidential and/or privileged material. >>If >> you received this email in error and are not the intended recipient, or >>the >> person responsible to deliver it to the intended recipient, please >>contact >> the sender at the email above and delete this email and any attachments >>and >> destroy any copies thereof. Any review, retransmission, dissemination, >> copying or other use of, or taking any action in reliance upon, this >> information by persons or entities other than the intended recipient is >> strictly prohibited. >> >> >> >>
