Thanks for the valuable feedback. @Stephan, you're totally right that the CEP DSLs and SQLs strongly resemble each other. It's probably mainly a question of syntax how a pattern definition can be exposed in stream SQL. For that we should take a closer look at Oracle's Pattern Matching extension on SQL. Thanks for the pointer @Paris. I included the reference into the design document.
I also agree that we should first concentrate on the pattern matching functionality. That way, we avoid duplicate work. This means implementing the NFA to detect event patterns and constructing this NFA from a pattern definition. I've created the umbrella JIRA ticket https://issues.apache.org/jira/browse/FLINK-3215 to track the overall progress of the CEP implementation. As first subtasks it includes the implementation of the pattern definition and the NFA. Cheers, Till On Sun, Jan 10, 2016 at 8:49 PM, Paris Carbone <par...@kth.se> wrote: > +1 for the cool design proposal. I also agree with Stephan’s point to > focus on the Pattern operator. > Ultimately in the future this could be merged into the SQL lib. There are > a few “standards" you could check out such as Oracle’s Pattern Matching > extension on SQL [1], apart from EPL. > > [1] https://docs.oracle.com/database/121/DWHSG/pattern.htm#DWHSG8956 > > > > On 10 Jan 2016, at 02:46, Henry Saputra <henry.sapu...@gmail.com<mailto: > henry.sapu...@gmail.com>> wrote: > > HI Till, > > Have you created JIRA ticket to keep track of this proposed new feature? > > We should create one to keep track updates on the effort. > > Thanks, > > Henry > > On Fri, Jan 8, 2016 at 6:54 AM, Till Rohrmann <trohrm...@apache.org > <mailto:trohrm...@apache.org>> wrote: > Hi everybody, > > recently we've seen an increased interest in complex event processing (CEP) > by Flink users. Even though most functionality is already there to solve > many use cases it would still be helpful for most users to have an easy to > use library. Having such a library which allows to define complex event > patterns would increase Flink's user range to the CEP community. Once > having laid the foundation, I'm optimistic that people will quickly pick it > up and further extend it. > > The major contribution of this library would be to add an efficient > non-deterministic finite automaton which can detect complex event patterns. > For everything else, Flink already has most of the functionality in place. > > I've drafted a design document for the first version. Please review it and > comment: > > > https://docs.google.com/document/d/15iaBCZkNcpqSma_qrF0GUyobKV_JttEDVuhNd0Y1aAU/edit?usp=sharing > > Thanks, > Till > >
