Hi all,
Flink doesn’t support the unnest() function, which takes an array and creates a
row for each element in the array. I have column containing an array of
map<str, str> and I’d like to implement my own unnest.
I try this as an initial do-nothing implementation:
@udtf(result_types=Datatypes.MAP(
key_type=Datatypes.STRING(), value_type=Datatypes.STRING()))
def my_unnest(arr):
return []
I get an error when Flink starts:
No match found for function signature my_unnest(<VARCHAR(2147483647),
VARCHAR(2147483647)) MAP ARRAY>)
Is there something that I’m missing in my definition please?
Many thanks,
John
