The document describes how transaction works and what the data layout is:
https://cwiki.apache.org/confluence/display/Hive/Hive+Transactions. See the
"Basic design" section. HDFS is immutable. Hive creates a delta directory for
every transaction and merges it when read, so it does not written to the same
block.
Wantao
At 2014-12-02 16:58:26, "unmesha sreeveni" <unmeshab...@gmail.com> wrote:
Why hive "UPADTE" is not reusing the blocks.
the update is not written to same block, why is it so ?
On Tue, Dec 2, 2014 at 10:50 AM, unmesha sreeveni <unmeshab...@gmail.com> wrote:
I tried to update my record in hive previous version and also tried out update
in hive 0.14.0. The newer version which support hive.
I created a table with 3 buckets with 180 MB. In my warehouse the data get
stored into 3 different blocks
delta_0000012_0000012
--- Block ID: 1073751752
--- Block ID: 1073751750
--- Block ID: 1073751753
After doing an update
I am getting 2 directories
delta_0000012_0000012
--- Block ID: 1073751752
--- Block ID: 1073751750
--- Block ID: 1073751753
AND
delta_0000014_0000014
---Block ID: 1073752044
Ie the blocks are not reused
Whether my understanding is correct?
Any pointers?
--
Thanks & Regards
Unmesha Sreeveni U.B
Hadoop, Bigdata Developer
Centre for Cyber Security | Amrita Vishwa Vidyapeetham
http://www.unmeshasreeveni.blogspot.in/
--
Thanks & Regards
Unmesha Sreeveni U.B
Hadoop, Bigdata Developer
Centre for Cyber Security | Amrita Vishwa Vidyapeetham
http://www.unmeshasreeveni.blogspot.in/
