Get it, thanks.
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Currently, this functionality is hard-coded in the aggregation
translation. Namely in
`org.apache.flink.table.runtime.aggregate.AggregateUtil#transformToAggregateFunctions`
[1].
Timo
[1]
https://github.com/apache/flink/blob/master/flink-libraries/flink-table/src/main/scala/org/apache/flink/t
Hi Timo,
Can you let me know how the build-in "MAX" function able to support
different types?
Thanks.
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Currently, there is no more flexible approch for aggregate functions.
Scalar functions can be overloaded but aggregate functions do not
support this so far.
Regards,
Timo
Am 07.01.19 um 02:27 schrieb yinhua.dai:
Hi Timo,
But getResultType should only return a concrete type information, righ
Hi Timo,
But getResultType should only return a concrete type information, right?
How could I implement with a generic type?
I'd like to clarify my questions again.
Say I want to implement my own "MAX" function, but I want to apply it to
different types, e.g. integer, long, double etc, so I tried
Hi Yinhua,
Flink needs to know how to serialize and deserialize a type `T`. If you
are using a type variable here, Flink can not derive the type information.
You need to override
org.apache.flink.table.functions.AggregateFunction#getResultType and
return type information that matches.
Rega
Hi Chesnay,
Maybe you misunderstand my question.
I have below code:
public class MyMaxAggregation extends AggregateFunction {
@Override
public MyAccumulator createAccumulator() {
return new MyAccumulator();
}
@Override
public T getValue(MyAccumulator accumulator) {
return null;
I believe you have to extend
"org.apache.flink.table.functions.AggregateFunction" instead for it to
work with SQL (or more generally speaking, any sub-class of
"org.apache.flink.table.functions.UserDefinedFunction".
On 04.01.2019 05:18, yinhua.dai wrote:
Hi Community,
I tried to write a UDF
Hi Community,
I tried to write a UDF with generic type, but seems that Flink will complain
not recognizing the type information when I use it in SQL.
I checked the implementation of native function "MAX" and realize that it's
not using the same API(AggregationFunction e.g.) as user defined functi
