`StreamTableEnvironment.create()` yields a `StreamTableEnvironmentImpl` object, which has several `registerFunction` interface for ScalarFunction/TableFunction/AggregateFunction/TableAggregateFunction.
`TableEnvironment.create()` yields a `TableEnvironmentImpl` object, which is a unify entry point for Table/SQL programs. And it only has a deprecated `registerFunction` interface for ScalarFunction. You should use `createTemporarySystemFunction` instead. A workaround for batch mode of blink planner is: You can use the public constructor of `StreamTableEnvironmentImpl` to create the TableEnvironment and use `registerFunction`s. Pls make sure you pass in the correct `isStreamingMode = false` *Best Regards,* *Zhenghua Gao* On Tue, Apr 14, 2020 at 5:58 PM Dmytro Dragan <dd...@softserveinc.com> wrote: > Hi All, > > > > Could you please tell how to register custom Aggregation function in blink > batch app? > > In case of streaming mode: > > We create > > EnvironmentSettings bsSettings = > EnvironmentSettings.*newInstance*().useBlinkPlanner().inStreamingMode().build(); > StreamTableEnvironment tableEnv = StreamTableEnvironment.*create*(env, > bsSettings); > > > > Which has: > > <T, ACC> void registerFunction(String name, AggregateFunction<T, ACC> > aggregateFunction); > > > > But in case of batchMode, we need to create TableEnvironment: > > > > EnvironmentSettings bsSettings = > EnvironmentSettings.*newInstance*().useBlinkPlanner().inBatchMode().build(); > tEnv = TableEnvironment.*create*(bsSettings); > > > > Which does not have this function to register AggregationFunction, only > Scalar one. > > > > Details: Flink 1.10, Java API > > > > >
