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 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 function,
is that the reason why "MAX" doesn't have the generic type issue?
How can I implement my own "MAX" function which could support all types?
Thanks.
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