json数据到配置单元堆大小错误

1l5u6lss  于 2021-06-26  发布在  Hive
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我正在处理使用nifi从facebook获得的嵌套json数据。我已经在配置单元中创建了一个表,并使用命令加载了数据。

CREATE TABLE abmediaanalysis (id string, posts struct< data:array<struct< message:string, shares:struct< count:int>, id:string, reactions:struct< data:array<struct< name:string,id:string>>, paging:struct< cursors:struct< before:string,after:string>, next:string>>, likes:struct< data:array<struct< id:string>>, paging:struct< cursors:struct< before:string,after:string>, next:string>>>>, paging:struct< previous:string,next:string>>, feed struct< data:array<struct< permalink_url:string,message:string,id:string>>, paging:struct< previous:string,next:string>>)ROW FORMAT SERDE 'org.openx.data.jsonserde.JsonSerDe';

load data local inpath '/home/10879/facebook1480479682880.json' overwrite into table abmediaanalysis;

我还添加了jar文件json-serde-1.3.8-jar-with-dependencies.jar,但是当我使用横向视图explode打印所有列时,得到了java堆大小错误。我也增加了堆的大小,但仍然有相同的错误

select id,posts_message,posts_share_count,posts_id,feed_data_permalink_url,feed_data_message,feed_data_id,reaction_data_name,reaction_data_id,posts_likes_data_id from abmediaanalysis
LATERAL VIEW explode(posts.data.message)MSG as posts_message
LATERAL VIEW explode(posts.data.shares.count)CT as posts_share_count
LATERAL VIEW explode(posts.data.id) I as posts_id
LATERAL VIEW explode(feed.data.permalink_url) PU as feed_data_permalink_url
LATERAL VIEW explode(feed.data.message) MSG as feed_data_message
LATERAL VIEW explode(feed.data.id) I as feed_data_id
LATERAL VIEW explode(posts.data.reactions) NM as posts_reactions_name
LATERAL VIEW explode(posts_reactions_name.data.name) NM as reaction_data_name
LATERAL VIEW explode(posts_reactions_name.data.id) NM as reaction_data_id
LATERAL VIEW explode(posts.data.likes) I as likes_data_id
LATERAL VIEW explode(likes_data_id.data.id) I as posts_likes_data_id;

当我试图打印两到三列而不是显示616条记录时,它显示了15625条记录。有人能帮助解决这个问题吗?有没有机会直接从nifi将上面的json数据加载到hive表中?如果是,你能告诉我吗。
提前谢谢

nkkqxpd9

nkkqxpd91#

如果我可以建议你另一种方法来加载整个 JSON 将字符串作为 String 外部表中的数据类型。
例如

CREATE EXTERNAL TABLE json_data_table (
    id String,
    json_data String
    )   
ROW FORMAT DELIMITED FIELDS TERMINATED BY '\u0001' LINES TERMINATED BY '\n' STORED AS TEXTFILE 
LOCATION '/path/to/json';

使用Hive get_json_object 提取单个列。例如
如果json\u数据列有以下json字符串

{"store":
  {"fruit":\[{"weight":8,"type":"apple"},{"weight":9,"type":"pear"}],
   "bicycle":{"price":19.95,"color":"red"}
  },
 "email":"amy@only_for_json_udf_test.net",
 "owner":"amy"
}

下面的查询获取

SELECT get_json_object(json_data, '$.owner') FROM json_data_table;

退货 amy 这样你就可以提取每一个 json 元素作为表中的列。

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