如何將數據複製到另一個表而不覆蓋現有列

Question

我在Amazon DynamoDB中有兩個表：元素和容器。層次結構是一個容器可以容納很少的元素。
所以元素看起來像：uuid，timestamp，container_id，data。
我想要聚合的所有元素的數據到對應的容器，例如：
元素：

| uuid | container_id | data | 
| 1 | 1   | 100 | 
| 2 | 1   | 150 | 
| 3 | 2   | 100 | 

所以我想在集裝箱表獲得：

| uuid | data | 
| 1 | 250 | 
| 2 | 100 | 

因此，使用蜂巢，我寫腳本（在EMR集羣上啓動）：

CREATE EXTERNAL TABLE element (`uuid` string, `container_id ` bigint, `data` double) STORED BY 'org.apache.hadoop.hive.dynamodb.DynamoDBStorageHandler' TBLPROPERTIES("dynamodb.table.name"="Elements", "dynamodb.column.mapping"="uuid:UUID,container_id:container_id,data:data"); 
CREATE EXTERNAL TABLE container (`uuid` string, `data` double) STORED BY 'org.apache.hadoop.hive.dynamodb.DynamoDBStorageHandler' TBLPROPERTIES("dynamodb.table.name"="Containers", "dynamodb.column.mapping"="uuid:UUID,data:data"); 
INSERT INTO TABLE container SELECT container_id as `uuid` sum(`data`) as `data` FROM element WHERE container_id IS NOT NULL GROUP BY container_id; 

它運作良好，但現在我需要寫e Containers表的一些額外數據，所以它應該像uuid, data, another_data。但是，當我在上面執行腳本時，它將覆蓋所有another_data（未在外部表中列出）。我嘗試了很多變體，但找不到解決方案。

Answer 1

好吧，我找到了答案：

CREATE EXTERNAL TABLE element (`uuid` string, `container_id ` bigint, `data` double) STORED BY 'org.apache.hadoop.hive.dynamodb.DynamoDBStorageHandler' TBLPROPERTIES("dynamodb.table.name"="Elements", "dynamodb.column.mapping"="uuid:UUID,container_id:container_id,data:data"); 
CREATE EXTERNAL TABLE container (`uuid` string, `data` double, `another_data` double) STORED BY 'org.apache.hadoop.hive.dynamodb.DynamoDBStorageHandler' TBLPROPERTIES("dynamodb.table.name"="Containers", "dynamodb.column.mapping"="uuid:UUID,data:data,another_data:another_data"); 
INSERT INTO TABLE container SELECT element.`container_id` as `uuid` sum(element.`data`) as `data`, collect_set(container.`another_data`)[0] as `another_data` FROM element LEFT JOIN container ON (element.`container_id` = container.`uuid`) WHERE element.container_id IS NOT NULL GROUP BY element.container_id;