Hi

Currently the encoding feature tries to avoid as much as duplicates in the row 
keys, family names, column qualifier names.  If there are two cells 

Row1/cf1:qual1/val1
Row1/cf1:qual2/val2 

Then we try to find the common part among both the keys.  The first key is 
stored as it is but in the second key we do not write the common part 'Row1 to 
qual' because the row and Cf are the same.  Even among the qualifier name we 
have 'qual' which is common.  

So if the key values have more repetitive parts we get better encoding.  So may 
be in the Phoenix layer if we find column names bigger and non-repetitive 
naming structure we could rename the column qualifiers to make use of the above 
encoding capability.

Regards
Ram

-----Original Message-----
From: James Taylor [mailto:[email protected]] 
Sent: Monday, January 19, 2015 10:30 PM
To: user
Subject: Re: short name for columns

Good idea. Phoenix doesn't do that today. I'm hoping that HBase can come up 
with better block encodings that factor this kind of information out without 
perf taking a hit. They actually have one (TRIE), but I'm not sure how stable 
it is. Also, I'm not sure how well the existing encodings do for this (maybe 
good enough?).

Please file a JIRA. Thanks,

James

On Mon, Jan 19, 2015 at 7:41 AM, Anil Gupta <[email protected]> wrote:
> You mean to have a support for aliases for columns?
> If yes, then +1 for that.
>
> Sent from my iPhone
>
> On Jan 19, 2015, at 3:49 AM, Bulvik, Noam <[email protected]> wrote:
>
> Hi,
>
>
>
> Do you plan to support assign short name for columns as part of 
> phoenix features. i.e. when creating table using phoenix DDL there 
> will be a metadata table that will convert the column name to short 
> names (like a,b,c … aa,bb….). each time there will be a query the SQL 
> that the user will use will be converted to the short name to query 
> the db and will be converted back to the real name in the result set.
>
>
>
> This may save a lot of space because the name of a column is part of 
> each row saved in the files.
>
>
>
> Regards,
>
> Noam
>
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