After "create index" command, you can use "update index index_name", index actually is a table itself. So you can see its contents and do other normal table operations.
Thanks, Yongqiang On 09-9-21 下午5:15, "Rutuja Raghoji" <[email protected]> wrote: > Hi, > Thanks for the fast reply. I have tried a lot to to find the index contens > and its location.Is there any way to see the contents of index? > > > > Regards, > Rutuja > > > From: He Yongqiang [[email protected]] > Sent: Monday, September 21, 2009 2:41 PM > To: [email protected] > Subject: Re: Indexing in hive > > Hi Rutuja, > Sorry, that patch is not ready yet. Will restart working on it from next > week. Sorry for the inconvenience. I will send you an email when the ready > patch is attached. Thanks for your attention. > > "Projection, Summary and Compact" > Projection, I think we may consider drop it. That's because in my lots of > recent experiments, projection does not speed much. > Summary is to record one index entry for every record. > Compact is to record only one index entry for all records with the same > index key. > > For example, we have three entries in table: > aa, abc, adc > aa, abcd, dd > > If we wants to use the first column as index key, > The summary index will look like: > aa, offset-of-first-record > aa, offset-of-second-record > > The compact index will look like: > aa, offset-of-first-record | offset-of-second-record > > Thanks, > yongqiang > On 09-9-21 下午4:55, "Rutuja Raghoji" <[email protected]> > wrote: > >> Hi, >> >> This query is with reference to the Indexing patch mentioned in the following >> link. >> >> https://issues.apache.org/jira/browse/HIVE-678 >> >> I applied the patch (hive-678-2009-07-25) on the Hive revision 796926 and >> built the code. >> >> Thereafter, created a small table pokes with two fields foo and bar and also >> created index on this table with type projection as follows. >> >> hive>CREATE TABLE pokes(foo int , bar string) ROW FORMAT DELIMITED FIELDS >> TERMINATED BY ','; >> >> hive>CREATE INDEX pokes_index1 TYPE PROJECTION ON TABLE pokes1(foo,bar); >> OK >> Time taken: 0.159 seconds >> >> hive> select a.* from pokes_index1 a; >> OK >> Time taken: 0.073 seconds >> >> As seen in the last query, I am not able to see the contents of index. Is >> there any way to see the contents of index table? >> >> Secondly, three kinds of indexes have been mentioned in the link namely, >> Projection, Summary and Compact. Could somebody explain the scenarions in >> which we can use them. >> DISCLAIMER >> ========== >> This e-mail may contain privileged and confidential information which is the >> property of Persistent Systems Ltd. It is intended only for the use of the >> individual or entity to which it is addressed. If you are not the intended >> recipient, you are not authorized to read, retain, copy, print, distribute or >> use this message. If you have received this communication in error, please >> notify the sender and delete all copies of this message. Persistent Systems >> Ltd. does not accept any liability for virus infected mails. >> >> > DISCLAIMER > ========== > This e-mail may contain privileged and confidential information which is the > property of Persistent Systems Ltd. It is intended only for the use of the > individual or entity to which it is addressed. If you are not the intended > recipient, you are not authorized to read, retain, copy, print, distribute or > use this message. If you have received this communication in error, please > notify the sender and delete all copies of this message. Persistent Systems > Ltd. does not accept any liability for virus infected mails. > >
