Hi Vadim, I would be interested in this too. Presently, I have to read my lookup source in the open method and keep it in a cache. By doing that I cannot make use of the broadcast state until ofcourse the first emit comes on the Broadcast stream. The problem with waiting the event stream is the lack of knowledge that I have read all the data from the lookup source. There is no possibility of having a special marker in the data as well for my use case. So pre loading the data seems to be the only option right now. Thanks, Chirag
On Friday, 8 February, 2019, 7:45:37 pm IST, Vadim Vararu <vadim.var...@adswizz.com> wrote: Hi all, I need to use the broadcast state mechanism (https://ci.apache.org/projects/flink/flink-docs-stable/dev/stream/state/broadcast_state.html) for the next scenario. I have a reference data stream (slow) and an events stream (fast running) and I want to do a kind of lookup in the reference stream for eachevent. The broadcast state mechanism seems to fit perfect the scenario. >From documentation:As an example where broadcast state can emerge as a natural >fit, one can imagine a low-throughput stream containing a set of rules which >we want to evaluate against all elements coming from another stream. However, I am not sure what is the correct way to delay the consumption of the fast running stream until the slow one is fully read (in case of a file) or until a marker is emitted (in case of some other source). Is there any way to accomplish that? It doesn't seem to be a rare use case. Thanks, Vadim.