Then you will get a copy of each sub table. My project use external partitions instead, and in this way, you don't need to cp sub tables. 1) Create a table some_table 2) ALTER TABLE some_table ADD PARTITION (partition_col = 'partition_col_value1') LOCATION '/user/data/subTable1' ALTER TABLE some_table ADD PARTITION (partition_col = 'partition_col_value2') LOCATION '/user/data/subTable2'
On Thu, Sep 13, 2012 at 4:23 AM, Bejoy KS <bejoy...@yahoo.com> wrote: > Hi > > Just follow the steps > 1) Create an external table with location as /user/aggregatedTable > 2) Move the contents of 3 monthly tables to this location > Hadoop fs -cp /user/monthlyTable1/* /user/aggregatedTable > > Hadoop fs -cp /user/monthlyTable2/* /user/aggregatedTable > > ... > > Replace the hsfs dirs in the above commands with those used in your tables. > Regards > Bejoy KS > > Sent from handheld, please excuse typos. > ________________________________ > From: zuohua zhang <zuo...@gmail.com> > Date: Wed, 12 Sep 2012 13:14:20 -0700 > To: <user@hive.apache.org>; <bejoy...@yahoo.com> > ReplyTo: user@hive.apache.org > Subject: Re: most efficient way to concatenate 3 tables into one? > > Thanks Bejoy. > Yes, they have the same schema. > Can you explain further how to? I am new to hive. > > > On Wed, Sep 12, 2012 at 1:06 PM, Bejoy KS <bejoy...@yahoo.com> wrote: >> >> Hi >> >> If all the 3 tables have the same. Schema, Create an external table and >> move the data from all the 3 tables to this new table's location. Just a >> hdfs copy or move is not that expensive. >> Regards >> Bejoy KS >> >> Sent from handheld, please excuse typos. >> ________________________________ >> From: zuohua zhang <zuo...@gmail.com> >> Date: Wed, 12 Sep 2012 13:02:42 -0700 >> To: <user@hive.apache.org> >> ReplyTo: user@hive.apache.org >> Subject: most efficient way to concatenate 3 tables into one? >> >> I have 3 tables, each contains monthly data, I would like to make a table >> to concatenate all 3 months into 1 table. >> What is the most efficient way to do that? >> I am using insert into which takes a long time. >> >> Thanks! > >
