将多个元素存储在 AWS Athena 的 json 文件中

Question

我有一些 json 文件存储在 S3 存储桶中，其中每个文件都有多个相同结构的元素。 例如，

[{"eventId":"1","eventName":"INSERT","eventVersion":"1.0","eventSource":"aws:dynamodb","awsRegion":"us-west-2","image":{"Message":"New item!","Id":101}},{"eventId":"2","eventName":"MODIFY","eventVersion":"1.0","eventSource":"aws:dynamodb","awsRegion":"us-west-2","image":{"Message":"This item has changed","Id":101}},{"eventId":"3","eventName":"REMOVE","eventVersion":"1.0","eventSource":"aws:dynamodb","awsRegion":"us-west-2","image":{"Message":"This item has changed","Id":101}}]

我想在 Athena 中创建一个与上述数据相对应的表。

我为创建表而编写的查询：

CREATE EXTERNAL TABLE IF NOT EXISTS sampledb.elb_logs2 (
  `eventId` string,
  `eventName` string,
  `eventVersion` string,
  `eventSource` string,
  `awsRegion` string,
  `image` map<string,string> 
)
ROW FORMAT SERDE 'org.openx.data.jsonserde.JsonSerDe'
WITH SERDEPROPERTIES (
  'serialization.format' = '1',
  'field.delim' = ' '
) LOCATION 's3://<bucketname>/';

但是，如果我按如下方式执行 SELECT 查询，

SELECT * FROM sampledb.elb_logs4;

我得到以下结果：

1   {"eventid":"1","eventversion":"1.0","image":{"id":"101","message":"New item!"},"eventsource":"aws:dynamodb","eventname":"INSERT","awsregion":"us-west-2"}   {"eventid":"2","eventversion":"1.0","image":{"id":"101","message":"This item has changed"},"eventsource":"aws:dynamodb","eventname":"MODIFY","awsregion":"us-west-2"}   {"eventid":"3","eventversion":"1.0","image":{"id":"101","message":"This item has changed"},"eventsource":"aws:dynamodb","eventname":"REMOVE","awsregion":"us-west-2"}   

json 文件的全部内容在这里被选为一个条目。

如何将 json 文件的每个元素作为一个条目读取？

编辑：如何读取图像的每个子列，即地图的每个元素？

谢谢。

Answer 1

问题 1：将多个元素存储在 AWS Athena 的 json 文件中

我需要将我的 json 文件重写为

{"eventId":"1","eventName":"INSERT","eventVersion":"1.0","eventSource":"aws:dynamodb","awsRegion":"us-west-2","image" :{"Message":"New item!","Id":101}}, {"eventId":"2","eventName":"MODIFY","eventVersion":"1.0","eventSource":" aws:dynamodb","awsRegion":"us-west-2","image":{"Message":"This item has changed","Id":101}}, {"eventId":"3", "eventName":"REMOVE","eventVersion":"1.0","eventSource":"aws:dynamodb","awsRegion":"us-west-2","image":{"Message":"此项已更改","Id":101}}

这意味着

去掉方括号 [ ] 将每个元素保持在一行

{.....................}
{.....................}
{.....................}

问题2。 访问非线性 json 属性

CREATE EXTERNAL TABLE IF NOT EXISTS <tablename> (
  `eventId` string,
  `eventName` string,
  `eventVersion` string,
  `eventSource` string,
  `awsRegion` string,
  `image` struct <`Id` : string,
                  `Message` : string>
)
ROW FORMAT SERDE 'org.openx.data.jsonserde.JsonSerDe'
WITH SERDEPROPERTIES (
  'serialization.format' = '1',
   "dots.in.keys" = "true"
) LOCATION 's3://exampletablewithstream-us-west-2/';

询问：

select image.Id, image.message from <tablename>;

参考：

http://engineering.skybettingandgaming.com/2015/01/20/parsing-json-in-hive/

https://github.com/rcongiu/Hive-JSON-Serde#mapping-hive-keywords