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Hive >> mail # user >> Hive select shows null after successful data load


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Re: Hive select shows null after successful data load
can you run a little more complex query

select uniq across columns or do some maths. so we know when it fires up a
mapreduce
On Wed, Jun 19, 2013 at 1:59 AM, Sunita Arvind <[EMAIL PROTECTED]>wrote:

> Thanks for responding Nitin. Yes I am sure that serde is working fine and
> json file is being picked based on all the errors that showed up till this
> stage. What sort of error are you suspecting. File not present or serde not
> parsing it ?
>
>
> On Tuesday, June 18, 2013, Nitin Pawar wrote:
>
>> select * from table is as good as hdfs -cat
>>
>> are you sure there is any data in the table?
>>
>>
>> On Tue, Jun 18, 2013 at 11:54 PM, Sunita Arvind <[EMAIL PROTECTED]>wrote:
>>
>>> Hi,
>>>
>>> I am able to parse the input JSON file and load it into hive. I do not
>>> see any errors with create table, so I am assuming that. But when I try to
>>> read the data, I get null
>>>
>>> hive> select * from jobs;
>>> OK
>>> null
>>>
>>> I have validated the JSON with JSONLint and Notepad++ JSON plugin and it
>>> is a valid JSON. Here is my create table statement and attached is the
>>> json input file.
>>>
>>> create external table jobs (
>>> jobs STRUCT<
>>> values : ARRAY<STRUCT<
>>> company : STRUCT<
>>> id : STRING,
>>> name : STRING>,
>>> postingDate : STRUCT<
>>> year : INT,
>>> day : INT,
>>> month : INT>,
>>> descriptionSnippet : STRING,
>>> expirationDate : STRUCT<
>>> year : INT,
>>> day : INT,
>>> month : INT>,
>>> position : STRUCT<
>>> title : STRING,
>>> jobFunctions : ARRAY<STRUCT<
>>> code : STRING,
>>> name : STRING>>,
>>> industries : ARRAY<STRUCT<
>>> code : STRING,
>>> id : STRING,
>>> name : STRING>>,
>>> jobType : STRUCT<
>>> code : STRING,
>>> name : STRING>,
>>> experienceLevel : STRUCT<
>>> code : STRING,
>>> name : STRING>>,
>>> id : STRING,
>>> customerJobCode : STRING,
>>> skillsAndExperience : STRING,
>>> salary : STRING,
>>> jobPoster : STRUCT<
>>> id : STRING,
>>> firstName : STRING,
>>> lastName : STRING,
>>> headline : STRING>,
>>> referralBonus : STRING,
>>> locationDescription : STRING>>>
>>>  )
>>> ROW FORMAT SERDE 'com.cloudera.hive.serde.JSONSerDe'
>>> LOCATION '/user/sunita/tables/jobs';
>>>
>>> The table creation works fine, but when I attempt to query, I get null
>>> as the result.
>>> I tried adding Input/Output formats, Serde Properties, nothing seems to
>>> impact.
>>>
>>> I am of the opinion that the libraries cannot handle this level of
>>> nesting and I probably will have to write a custom serde or a parser
>>> myself. Just wanted to seek guidance before I get into that. Appreciate
>>> your help and guidance.
>>>
>>> regards
>>> Sunita
>>>
>>
>>
>>
>> --
>> Nitin Pawar
>>
>
--
Nitin Pawar