在 AWS Athena 的 json 文件中存储多个元素

Posted 2023-02-16

【中文标题】在 AWS Athena 的 json 文件中存储多个元素

【英文标题】：Store multiple elements in json files in AWS Athena

【发布时间】：2017-06-21 09:44:47

【问题描述】：

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对应的表。

我为创建表编写的查询：

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>/';

但如果我按如下方式进行 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。

【参考方案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":"新项目！","Id":101, "eventId":"2","eventName":"MODIFY","eventVersion":"1.0","eventSource ":"aws:dynamodb","awsRegion":"us-west-2","image":"Message":"该项目已更改","Id":101, "eventId":" 3","eventName":"REMOVE","eventVersion":"1.0","eventSource":"aws:dynamodb","awsRegion":"us-west-2","image":"Message": "此项目已更改","Id":101

意思是

去掉方括号 [ ] 让每个元素在一行中

.....................
.....................
.....................

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/';

查询：

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

【讨论】：

我和 Q1 有同样的问题，因为我的数据来自 sendgrid，我对数据格式没有太多选择:(

您是否能够告诉 kinesis firehose 在一个 S3 文件中的每个条目后放置一个新行？