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HBase >> mail # dev >> Cell Encoders and usage of Cell

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Re: Cell Encoders and usage of Cell
On Wed, Apr 17, 2013 at 10:16 AM, ramkrishna vasudevan <

> Hi
> With the introduction of the new Cell Interface we are providing a way
> where both the RPC usage of cell and the usage of Cell in HFile are
> unified.(abstracted)
> The current block encoder which encodes the kvs into hfile blocks will be
> enhanced may be BlockEncode2 which will deal with Cell encoding and the
> same will be written to HFile.
That is the idea.  Current block encoders are unusable for anything but
hfile with their presumption of a particular KeyValue serialization and
 with hfile context sprinkled throughout.

> Does that mean that there are going to be changes to the HFile format also?
>  Just to understand is my understanding here correct or not.
I think so.  hfile APIs are about KVs.  Should be about Cell I'd think.

> Because as the Cell interface the row, family, qualifier all are treated as
> individual byte arrays.  Also it does not provide a way to access the
> getKeyOffset() and getKeyLength().
If you need the above, you are no doing Cell right I'd argue.  The very
idea of Cell is a disconnect between how it is stored and Cell use.
> This is in lieu with HBASE-7448 - Adding tags to cell interface and then
> the same will  be used in
> HBASE-7663 - Visibility labels.
I am not sure I follow what you are asking above Ram.  I think the Cell
Interface needs methods added to allow access to "labels".

> May be further queries/doubts can be posted on those relevant JIRAs to
> proceed work on that.
> Regards
> Ram