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HBase, mail # user - Replication is on columnfamily level or table level?


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Re: Replication is on columnfamily level or table level?
Shahab Yunus 2013-06-05, 12:34
Anoop, Can you please clarify a bit.

-So we can specify replication at CF level but the scope 2 is not
supported, right? And we can replicate one CF to one slave cluster and
other CF to other slave cluster? Right? Thanks.

Regards,
Shahab
On Wed, Jun 5, 2013 at 12:37 AM, Anoop John <[EMAIL PROTECTED]> wrote:

> Yes the replication can be specified at the CF level..  You have used
> HCD#setScope() right?
>
> > S => '3', BLOCKSIZE => '65536'}, {*NAME => 'cf2', REPLICATION_SCOPE =>
> '2'*,
> You set scope as 2?? You have to set one CF to be replicated to one cluster
> and another to to another cluster. I dont think it is supported even now.
> You can see in the HCD code that there are 2 constants for scope 0 and 1
> where 1 means replicate and 0 means not to be  replicated.
>
> -Anoop-
>
> On Wed, Jun 5, 2013 at 3:31 AM, N Dm <[EMAIL PROTECTED]> wrote:
>
> > hi, folks,
> >
> > <hbase 0.94.3>
> >
> > By reading several documents, I always have the impression that *
> > "Replication* works at the table-*column*-*family level*". However, when
> I
> > am setting up a table with two columnfamilies and replicate them to two
> > different slavers, the whole table replicated. Is this a bug? Thanks
> >
> > Here is the simple steps to receate.
> >
> > *Environment: *
> > Replication Master: hdtest014
> > Replication Slave 1: hdtest017
> > Replication Slave 2: hdtest009
> >
> > *Create Table*: on Master, and the two slaves:  create
> 't2_dn','cf1','cf2'
> >
> > *setup replication on Master*(hdtest014), so that
> > Master> list_peers
> >  PEER_ID CLUSTER_KEY STATE
> >  1 hdtest017.svl.ibm.com:2181:/hbase ENABLED
> >  2 hdtest009.svl.ibm.com:2181:/hbase ENABLED
> > Master> > describe 't2_dn'
> > DESCRIPTION
> > ENABLED
> >  {NAME => 't2_dn', FAMILIES => [{*NAME => 'cf1', REPLICATION_SCOPE =>
> '1'*,
> > KEEP_DELETED_CELLS => 'fals
> > true
> >  e', COMPRESSION => 'NONE', ENCODE_ON_DISK => 'true', BLOCKCACHE =>
> 'true',
> > MIN_VERSIONS => '0',
> > DATA
> >  _BLOCK_ENCODING => 'NONE', IN_MEMORY => 'false', BLOOMFILTER => 'NONE',
> > TTL => '2147483647',
> > VERSION
> >  S => '3', BLOCKSIZE => '65536'}, {*NAME => 'cf2', REPLICATION_SCOPE =>
> > '2'*,
> > KEEP_DELETED_CELLS =>
> > 'fa
> >  lse', COMPRESSION => 'NONE', ENCODE_ON_DISK => 'true', BLOCKCACHE =>
> > 'true', MIN_VERSIONS => '0',
> > DA
> >  TA_BLOCK_ENCODING => 'NONE', IN_MEMORY => 'false', BLOOMFILTER =>
> 'NONE',
> > TTL => '2147483647',
> > VERSI
> >  ONS => '3', BLOCKSIZE =>
> > '65536'}]}
> >
> > 1 row(s) in 0.0250 seconds
> >
> > *Put rows into t2_dn on Master*
> > put 't2_dn','row1','cf1:q1','val1cf1fromMaster'
> > put 't2_dn','row1','cf2:q1','val1cf2fromMaster'
> > put 't2_dn','row2','cf1:q1','val2cf1fromMaster'
> > put 't2_dn','row3','cf2:q1','val3cf2fromMaster'
> >
> > *Expecting cf1 replicated to slave1, and cf2 replicatedto slave2. Where
> all
> > the three clusters got: *
> > scan 't2_dn'
> > ROW
> > COLUMN+CELL
> >
> >  row1                          column=cf1:q1, timestamp=1370382328358,
> > value=val1cf1fromMaster
> >  row1                          column=cf2:q1, timestamp=1370382334303,
> > value=val1cf2fromMaster
> >  row2                          column=cf1:q1, timestamp=1370382351716,
> > value=val2cf1fromMaster
> >  row3                          column=cf2:q1, timestamp=1370382367724,
> > value=val3cf2fromMaster
> > 3 row(s) in 0.0160 seconds
> >
> > Many thanks
> >
> > Demai
> >
>