{ "_yql_read_udf"="DummyLog.ReadRecord2"; "_yql_read_udf_type_config"="AAA"; "_yql_read_udf_run_config"="BBB"; "_yql_row_spec" = { "Type" = [ "StructType"; [ [ "key"; [ "DataType"; "String" ] ]; [ "subkey"; [ "DataType"; "String" ] ]; [ "value"; [ "DataType"; "String" ] ] ] ] } }