The problem with defining a UDF is that you have to create one overload per key type in the MULTISET. It would be very convenient to have functions like Snowflakes ARRAY_AGG.
On Sat, Sep 18, 2021, 05:43 JING ZHANG <beyond1...@gmail.com> wrote: > Hi Kai, > AFAIK, there is no built-in function to extract the keys in MULTISET > <https://ci.apache.org/projects/flink/flink-docs-release-1.13/docs/dev/table/types/> > to > be an ARRAY. Define a UTF is a good solution. > > Best, > JING ZHANG > > Kai Fu <zzfu...@gmail.com> 于2021年9月18日周六 上午7:35写道： > >> Hi team, >> >> We want to know if there is any built-in function to extract the keys in >> MULTISET >> <https://ci.apache.org/projects/flink/flink-docs-release-1.13/docs/dev/table/types/> >> to be an ARRAY. There is no such function as far as we can find, except to >> define a simple wrapper UDF for that, please advise. >> >> -- >> *Best wishes,* >> *- Kai* >> >
