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Hive >> mail # user >> Describe extended shows number of rows as 0


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Aishwarya Ganesan 2013-05-02, 14:24
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Sanjay Subramanian 2013-05-02, 14:30
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Aishwarya Ganesan 2013-05-02, 14:40
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Re: Describe extended shows number of rows as 0
I changed hive-site.xml to use mysql datastore.

*Still no of rows is 0. Whereas column statistics are populated*. And both
table and column statistics are using the same store.

Querying the mysql store for statistics.

select * from TABLE_PARAMS;
+--------+-----------------------+-------------+
| TBL_ID | PARAM_KEY             | PARAM_VALUE |
+--------+-----------------------+-------------+
|      1 | numFiles                         | 2           |
|      1 | numPartitions                  | 0           |
|      1 | numRows                        | 0           |
|      1 | rawDataSize                    | 0           |
|      1 | totalSize                         | 708621      |
|      1 | transient_lastDdlTime | 1367562429  |
+--------+-----------------------+-------------+
select
COLUMN_NAME,COLUMN_TYPE,LONG_HIGH_VALUE,LONG_LOW_VALUE,NUM_DISTINCTS,TABLE_NAME
from TAB_COL_STATS;
+--------------+-------------+-----------------+----------------+---------------+------------+
| COLUMN_NAME  | COLUMN_TYPE | LONG_HIGH_VALUE | LONG_LOW_VALUE |
NUM_DISTINCTS | TABLE_NAME |
+--------------+-------------+-----------------+----------------+---------------+------------+
| l_orderkey                | int                  |
5988 |                              0 |                        28 |
lineitem2  |
| l_linenumber             | int                  |
     7 |                              0 |                        15 |
lineitem2  |
+--------------+-------------+-----------------+----------------+---------------+------------+
--
Thanks,
Aishwarya

On Thu, May 2, 2013 at 8:10 PM, Aishwarya Ganesan <[EMAIL PROTECTED]>wrote:

> Also, When i run
>
> ANALYZE TABLE lineitem1 COMPUTE STATISTICS FOR COLUMNS L_LINENUMBER;
>
> and check the column statistics values, they are populated correctly. Only
> number of row information is wrong. How is this possible?
>
>
> On Thu, May 2, 2013 at 8:00 PM, Sanjay Subramanian <
> [EMAIL PROTECTED]> wrote:
>
>>  Not that it could be related but if possible setup a Mysql or similar
>> serious datastore….that Hive can connect to…
>>
>>  Its possibly not prudent spending time to analyze problems caused  by
>> derby metastore and with Mysql u can start doing some heavy duty stinging
>> with Hive :-)
>> Regards
>> sanjay
>>
>>   From: Aishwarya Ganesan <[EMAIL PROTECTED]>
>> Reply-To: "[EMAIL PROTECTED]" <[EMAIL PROTECTED]>
>> Date: Thursday, May 2, 2013 7:24 AM
>> To: "[EMAIL PROTECTED]" <[EMAIL PROTECTED]>
>> Subject: Describe extended shows number of rows as 0
>>
>>
>> Hi,
>>
>> When  I run analyze table command and run describe extended command, it
>> shows the number of rows as 0.
>>
>> Query: DESCRIBE EXTENDED lineitem1;
>>
>> Result:
>>
>> .......parameters:{numPartitions=0, numFiles=4,
>> transient_lastDdlTime=1367502213, numRows=0, totalSize=3184, rawDataSize=0},
>>
>> My Settings:
>>       <property>
>>                 <name>javax.jdo.option.ConnectionURL</name>
>>
>> <value>jdbc:derby:;databaseName=/home/TempStatsStore;create=true</value>
>>                 <description>JDBC connect string for a JDBC
>> metastore</description>
>>         </property>
>>
>> How to resolve this?
>>
>>
>>
>> Thanks,
>> Aishwarya
>>
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>
>
>
> --
> Thanks,
> Aishwarya