Question

尝试使用 elephant-bird JsonLoader 加载其中包含空值的json文件。

sample.json

{"created_at": "Mon Aug 22 10:48:23 +0000 2016","id": 767674772662607873,"id_str": "767674772662607873","text": "KPIT Image Result for https:\/\/t.co\/Nas2ZnF1zZ... https:\/\/t.co\/9TnelwtIvm","source": "\u003ca href=\"http:\/\/twitter.com\" rel=\"nofollow\"\u003eTwitter Web Client\u003c\/a\u003e","truncated": false,"in_reply_to_status_id": 123,"in_reply_to_status_id_str": null,"in_reply_to_user_id": null,"in_reply_to_user_id_str": null,"in_reply_to_screen_name": null,"geo": null,"coordinates": null,"place": null,"contributors": null,"is_quote_status": false,"retweet_count": 0,"favorite_count": 0,"entities": {"hashtags": [],"urls": [{"url": "https:\/\/t.co\/Nas2ZnF1zZ","expanded_url": "http:\/\/miltonious.com\/","display_url": "miltonious.com","indices": [24, 47]}],"user_mentions": [],"symbols": []},"favorited": false,"retweeted": false,"possibly_sensitive": false,"filter_level": "low","lang": "en","timestamp_ms": "1471862903167"}

脚本：

REGISTER piggybank.jar
REGISTER json-simple-1.1.1.jar
REGISTER elephant-bird-pig-4.3.jar
REGISTER elephant-bird-core-4.1.jar
REGISTER elephant-bird-hadoop-compat-4.3.jar

json = LOAD 'sample.json' USING JsonLoader('created_at:chararray, id:chararray, id_str:chararray, text:chararray, source:chararray, in_reply_to_status_id:chararray, in_reply_to_status_id_str:chararray, in_reply_to_user_id:chararray, in_reply_to_user_id_str:chararray, in_reply_to_screen_name:chararray, geo:chararray, coordinates:chararray, place:chararray, contributors:chararray, is_quote_status:bytearray, retweet_count:long, favorite_count:chararray, entities:map[], favorited:bytearray, retweeted:bytearray, possibly_sensitive:bytearray, lang:chararray');

describe json;
dump json;

当我转储json时，我得到以下输出和 worning

（星期一8月22日10:48:23 +0000 2016,767674772662607873,767674772662607873，Twitter Web客户端的Google图片搜索结果，false，1234,12345,3214,43215 ,,,,,,,,,, ,,,,）

WARN org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigHadoopLogger - org.apache.pig.builtin.JsonLoader（UDF_WARNING_1）：错误记录，{complete json}返回null

通过警告我猜它是获得NULL值。那么我们如何加载一个具有空值的Json。

我尝试过另一种方式，即

json = LOAD 'sample.json' USING com.twitter.elephantbird.pig.load.JsonLoader('created_at:chararray, id:chararray, id_str:chararray, text:chararray, source:chararray, in_reply_to_status_id:chararray, in_reply_to_status_id_str:chararray, in_reply_to_user_id:chararray, in_reply_to_user_id_str:chararray, in_reply_to_screen_name:chararray, geo:chararray, coordinates:chararray, place:chararray, contributors:chararray, is_quote_status:bytearray, retweet_count:long, favorite_count:chararray, entities:map[], favorited:bytearray, retweeted:bytearray, possibly_sensitive:bytearray, lang:chararray');

describe json;

输出

Schema for json unknown.

请建议我。

感谢。

Answer 1

您可以尝试这样的事情，

 MY_JSON = LOAD 'sample.json' USING com.twitter.elephantbird.pig.load.JsonLoader('-nestedLoad');
 dump MY_JSON;

无法使用Elephant Bird

1 个答案: