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HBase, mail # user - Disable timestamp in HBase Table a.k.a Disable Versioning in HBase Table


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Re: Disable timestamp in HBase Table a.k.a Disable Versioning in HBase Table
Matt Corgan 2012-05-25, 06:22
Hi Anil,

I created HBASE-6093
<https://issues.apache.org/jira/browse/HBASE-6093>with an idea that
could solve this problem.  It could be a simple
implementation for simple workloads, but gets harder to support for tables
with TTL's, maxVersion > 1, Deletes, etc...  Maybe it can only be enabled
if the other ColumnFamily settings are compatible.

Matt
On Thu, May 24, 2012 at 9:37 PM, Ted Yu <[EMAIL PROTECTED]> wrote:

> What Anoop said is in 0.94.0
>
> For trunk, HBASE-4676 provides trie data block encoding.
> It suits write-once read-many use case very well.
>
> Cheers
>
> On Thu, May 24, 2012 at 5:57 PM, Anoop Sam John <[EMAIL PROTECTED]>
> wrote:
>
> > Hi Anil,
> >           There is no way you can avoid the timestamp with KVs. In your
> > case you can think of using data block encoding? You can see
> > FastDiffDeltaEncoder and DiffKeyDeltaEncoder. This includes way of
> avoiding
> > writing the 8 bytes into each KV for timestamp. Still some bytes will be
> > written though and this will be done at the block level. Also pls note
> that
> > these encoders will do much more things than the timestamp space
> > optimization. Also you need to make sure to pass some timestamp in your
> > Puts. May be better make as 0L. Else in RS side HBase will assign the cur
> > time as the timestamp.  Hope when u read the javadoc for these encoder
> > classes, u will be more clear.
> >
> > The one you are telling abt having a feature to fully avoid the timestamp
> > is a topic to discuss
> >
> > Hope I make it clear to you
> >
> > -Anoop-
> > ________________________________________
> > From: anil gupta [[EMAIL PROTECTED]]
> > Sent: Friday, May 25, 2012 3:21 AM
> > To: [EMAIL PROTECTED]
> > Subject: Disable timestamp in HBase Table a.k.a Disable Versioning in
> > HBase Table
> >
> > Hi All,
> >
> > We are planning to store data in HBase. Currently, in one of our use case
> > once a row is written into HBase Table we wont be modifying the data of
> > that row. Since, for every cell(right?) in HBase a timestamp(long value)
> is
> > stored; this would take up extra 8 bytes. I was thinking is there a way
> to
> > disable timestamp on HBase table when versioning is not required. I went
> > through the documentation and searched mailing list for same but could
> not
> > find anything relevant. Since we are talking about billions of cells,
> this
> > would add up to significant amount of space.(around 7.45 GigaBytes for 1
> > billion cells). Does this sounds like a feature HBase is missing?
> >
> > Please share your thoughts.
> >
> > --
> > Thanks & Regards,
> > Anil Gupta
> >
>