Thanks James
Any explanation to why do we see this difference after all we are writing the 
same data in both cases

-----Original Message-----
From: James Taylor [mailto:jamestay...@apache.org]
Sent: Tuesday, March 10, 2015 11:08 AM
To: user
Subject: Re: CSV bulk loading question

Hi Noam,
We're tuning CSV bulk load in PHOENIX-1711, but it won't get you a 7x speedup 
(maybe 30% at the most if we're lucky). The other thing you'd lose by writing 
all values into one column is incremental update speed which may or may not 
apply for your use case. To update a single value, you'd need to read the 
existing value, stitch in the new value and write it back out again.

If your use case doesn't require incremental update, you can write them all in 
a single column and still query and access them individually. The easiest way I 
can think of doing this would be to store them in a protobuf and serialize it 
into a VARBINARY column.
Then create a built-in function that allows accessing them positionally or by 
name. Once you have that, could even add functional indexes over individual 
fields (obviously with the overhead that indexes add). PHOENIX-477 is about 
formalizing this as SQL Structs which this could become if taken far enough. 
Even without this, just having a set of built-in functions that work off of a 
protobuf would be a useful first step and a great contribution.

Thanks,
James


On Mon, Mar 9, 2015 at 11:03 PM, Bulvik, Noam <noam.bul...@teoco.com> wrote:
> Hi,
>
>
>
> We are using the CSV bulk  loading (MR) to load our data. we have a
> table with 50 columns and We did some testing to understand the
> factors on the performance of loading.
>
> We compared two cases
>
> A -  each column in the data will be a column in hbase table
>
> B – take all non-key column and put them in one column in the hbase
> table
>
>
>
> We saw that the second option we 7 times faster than the first one and
> consumed les CPU resources.
>
>
>
> Does this make sense? Can we do something to tune the system so option
> A will run faster? (we prefer it this way because it enables us to
> query and filter over all data columns)
>
>
>
>
>
> Regards,
>
>
>
> Noam Bulvik
>
>
>
>
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