Pyflink UDF with ARRAY as input

[Barth, Torben]

Dear List,

I have  a table with the following structure

my_table
-- Key: String
-- List_element: ARRAY<ROW<`integer_element` INT, `string_element` STRING >>

I want to define a udf to extract information of the “list_element”. I do not 
manage to access the information of the array in the udf. I try something like:

@udf(result_type=DataTypes.STRING())
def get_string_element(my_list):
       my_string = ‘xxx’
        for element in my_list:
            if element.integer_element  == 2:
                my_string = element. string_element
        return my_string


table_env.create_temporary_function("get_string_element", get_string_element)
# use the function in Python Table API
my_table.select("get_string_element(List_element)")

Unfortunately, I cannot get it work. Does anybody have an idea how the correct 
way to extract the information is?

Any comments or ideas are very welcome.

Thanks
Torben

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