エラー・・・ 0: jdbc:drill:zk=local> SELECT FLATTEN(KVGEN(t.GET_STATS_LIST.DATALIST_INF)) FROM dfs.`/tmp/stats_list.json` t;! Error: SYSTEM ERROR: org.apache.drill.common.exceptions.DrillRuntimeException: Ma ppify/kvgen does not support heterogeneous value types. All values in the input m ap must be of the same type. The field [`unknown`] has a differing type [minor_ty pe: LATE! mode: OPTIONAL! ].! ! Fragment 0:0! ! [Error Id: e5f8f642-d03d-4d95-b2d9-e2b47289dee6 on 192.168.111.11:31010] (state=, code=0)!