Hi Guobao, Are you using table API? I'm not familiar with table API, but for data stream API, generally speaking user could do some initialization through "open" method of "Rich" function, like "RichAggregateFunction".
Thanks, Biao /'bɪ.aʊ/ On Tue, 3 Dec 2019 at 22:44, Guobao Li <gu...@criteo.com> wrote: > Hi community, > > > > I am trying to register a metric in an aggregate UDF by overriding the > *open* function. According to the documentation, the *open* function can > be override in order to retrieve the metric group to do the metric > registration. But it works only on ScalarFunction not on AggregateFunction. > Since the *open* function is not invoked by AggregateFunction. Could > anyone help me out of it? > > > > Thanks, > > Guobao > > >
