Jasper Knulst created HIVE-8871:
-----------------------------------

             Summary: Hive Hbase Integration : Support for NULL value  columns
                 Key: HIVE-8871
                 URL: https://issues.apache.org/jira/browse/HIVE-8871
             Project: Hive
          Issue Type: Bug
          Components: HBase Handler
    Affects Versions: 0.10.0
            Reporter: Jasper Knulst


If you map Hive to a Hbase table where one CF only has qualifiers but no 
values, Hive always outputs ' {} ' for that key. As soon as you put a single 
byte (like a space) as value you'll get a return like this ' {"20140911"," "}.



Since it is a common data modelling technique in Hbase to not use the value 
(and essentially use the qualifier in a CF as value holder) I think it would be 
worthwhile to have some support for this in the Hbase handler. 

A solution could be to show a data structure like  CF:qualifier:<NULL> like 
this: {"20140911",""}
, where '20140911' is the qualifier and NULL value in Hbase are shown as empty 
json strings.

CREATE EXTERNAL TABLE hb_test (
  userhash string,
  count bigint,
  dates map<string,string>)
STORED BY 'org.apache.hadoop.hive.hbase.HBaseStorageHandler'
WITH SERDEPROPERTIES (
  "hbase.columns.mapping" =
  ":key,SUM:COUNT,DATES:",
"hbase.table.default.storage.type" = "binary"
)
TBLPROPERTIES("hbase.table.name" = "test");



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