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From onmstester onmstester <onmstes...@zoho.com>
Subject Re: copy from one table to another
Date Mon, 09 Apr 2018 03:09:47 GMT
Thank you all

I need something like this:

insert into table test2 select * from test1 where partition_key='SOME_KEYS';

The problem with copying sstable is that original table contains some billions of records
and i only want some hundred millions of records from the table, so after copy/pasting big
sstables in so many nodes i should wait for a deletion that would take so long to response:

delete from test2 where partition_key != 'SOME_KEYS'


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---- On Mon, 09 Apr 2018 06:14:02 +0430 Dmitry Saprykin &lt;saprykin.dmitry@gmail.com&gt;
wrote ----




IMHO The best step by step description of what you need to do is here



https://issues.apache.org/jira/browse/CASSANDRA-1585?focusedCommentId=13488959&amp;page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-13488959



The only difference is that you need to copy data from one table only. I did it for a whole
keyspace.










On Sun, Apr 8, 2018 at 3:06 PM Jean Carlo &lt;jean.jeancarl48@gmail.com&gt; wrote:






You can use the same procedure to restore a table from snapshot from datastax webpage 



https://docs.datastax.com/en/cassandra/2.1/cassandra/operations/ops_backup_snapshot_restore_t.html


Just two modifications.




after step 5, modify the name of the sstables to add the name of the table you want to copy
to.




and in the step 6 copy the sstables to the right directory corresponding to the tale you want
to copy to.




Be sure you have an snapshot of the table source and ignore step 4 of course 






Saludos



Jean Carlo


"The best way to predict the future is to invent it" Alan Kay






On Sun, Apr 8, 2018 at 6:33 PM, Dmitry Saprykin &lt;saprykin.dmitry@gmail.com&gt;
wrote:

You can copy hardlinks to ALL SSTables from old to new table and then delete part of data
you do not need in a new one.



On Sun, Apr 8, 2018 at 10:20 AM, Nitan Kainth &lt;nitankainth@gmail.com&gt; wrote:

If it for testing and you don’t need any specific data, just copy a set of sstables with
all files of that sequence and move to target tables directory and rename it.



Restart target node or run nodetool refresh 



Sent from my iPhone



On Apr 8, 2018, at 4:15 AM, onmstester onmstester &lt;onmstester@zoho.com&gt; wrote:


Is there any way to copy some part of a table to another table in cassandra? A large amount
of data should be copied so i don't want to fetch data to client and stream it back to cassandra
using cql.



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