Hi, what you can also do is use a RichMapFunction. Rich functions have open()/close() methods that get called before the first element and the last element, respectively. See here https://ci.apache.org/projects/flink/flink-docs-master/apis/common/index.html#specifying-transformation-functions for more information.
Cheers, Aljoscha On Tue, 10 May 2016 at 07:31 milind parikh <milindspar...@gmail.com> wrote: > I am new to flink. I am wondering what the best practice is for looking up > additional values for entities embedded in an event. > > For example, an event might have the engine model #. A metadata store has > the typical rpm characteristics of an engine model #; which can be used in > a subsequent processing of the event. I call the process of event > inflation "event adornment". Currently I use a Map function transformation > to do the lookup in the Map function through instatiating a connection in > the Map function to the Metadata store per map execution. The thing works; > however having 100K connections is not very ideal (assuming 100k eps). Any > alternative ideas; given the implementing class has to be Serializable? >
