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Hive >> mail # user >> num_rows is always 0 in statistics


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RE: num_rows is always 0 in statistics
I resolved the issue with following way.

Configure
"hive.stats.dbconnectionstring=jdbc:derby:;databaseName=/home/TempStore".
This works only in single node cluster.
Please check HIVE-3324.
-----Original Message-----
From: Hiroyuki Yamada [mailto:[EMAIL PROTECTED]]
Sent: Wednesday, August 29, 2012 11:57 AM
To: [EMAIL PROTECTED]
Subject: num_rows is always 0 in statistics

Hi,

I have run "analyse table" command several times to get statistics,
but I always get num_rows=0 like below.
(also, raw_data_size is 0)

-----
hive> analyze table lineitem compute statistics;
Total MapReduce jobs = 1
Launching Job 1 out of 1
Number of reduce tasks is set to 0 since there's no reduce operator
Starting Job = job_201208291425_0011, Tracking URL http://hadoop-node1:50030/jobdetails.jsp?jobid=job_201208291425_0011
Kill Command = /usr/lib/hadoop-0.20/bin/hadoop job
-Dmapred.job.tracker=hadoop-node1:8021 -kill job_201208291425_0011
Hadoop job information for Stage-0: number of mappers: 3; number of
reducers: 0
2012-08-29 15:16:16,133 Stage-0 map = 0%,  reduce = 0%
2012-08-29 15:16:20,154 Stage-0 map = 100%,  reduce = 0%
2012-08-29 15:16:22,168 Stage-0 map = 100%,  reduce = 100%
Ended Job = job_201208291425_0011
Table sf1.lineitem stats: [num_partitions: 0, num_files: 1, num_rows:
0, total_size: 759863287, raw_data_size: 0]
-----

I tried the version 0.7.1, 0.8.1, 0.9.0 and
the same result.
Is there anything else I have to do to make it work ?

Also, is statistics only works for managed tables ?
I tried it for external tables and it doesn't seem working. (all the
values are 0 )

Thanks,

Hiroyuki