Question

我是HIVE的新手，需要一些帮助来查询我从JSON文件创建的表格。

CREATE TABLE json_table( json string);
LOAD DATA INPATH  '/path/to/file.json' 
INTO TABLE json_table;

当我用：

查询创建的json_table.json时

SELECT * FROM json_table;

返回：

{"id":243379853,"sampling_rate":null,"timestamp":"2017-08-06 20:05:02","location":{"id":1296,"latitude":"49.863","longitude":"8.651","country":"DE"},"sensor":{"id":2573,"pin":"7","sensor_type":{"id":9,"name":"DHT22","manufacturer":"various"}},"sensordatavalues":[{"id":559959584,"value":"19.00","value_type":"temperature"},{"id":559959585,"value":"86.00","value_type":"humidity"}]}

我正在尝试获得像

这样的结果

id        | timestampt |         | [...] | 
==========|======================|=======| 
243379853 | 2017-08-06 20:05:02  | [...] |

带有查询

SELECT
  GET_JSON_OBJECT(json_table.json,'$.id'),
  GET_JSON_OBJECT(json_table.json,'$.timestamp')
  GET_JSON_OBJECT(json_table.json,'$.sampling_rate')
  GET_JSON_OBJECT(json_table.json,'$.location.latitude')
  GET_JSON_OBJECT(json_table.json,'$.location.longitude')
FROM json_table;

但我得到以下Hive SQL Exception

java.lang.Exception：org.apache.hive.service.cli.HiveSQLException：编译语句时出错：FAILED：ParseException line 4:17 EOF at'（'near'GET_JSON_OBJECT'

Answer 1

您需要添加逗号：

SELECT
  GET_JSON_OBJECT(json_table.json,'$.id'),
  GET_JSON_OBJECT(json_table.json,'$.timestamp'),   --here
  GET_JSON_OBJECT(json_table.json,'$.sampling_rate'), --here
  GET_JSON_OBJECT(json_table.json,'$.location.latitude'), -- and here
  GET_JSON_OBJECT(json_table.json,'$.location.longitude')
FROM json_table;

我还会使用expr AS alias为列添加别名。

在JSON上查询Hive的EOF异常

1 个答案: