accumulo-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From dlmar...@comcast.net
Subject Re: Writing data from iterators
Date Tue, 29 Apr 2014 14:24:42 GMT
One reason that I can think of is that there is not a close() method on the iterator interface.
If you had resources open, you won't know when to clean them up. 


----- Original Message -----

From: "Donald Miner" <dminer@clearedgeit.com> 
To: dev@accumulo.apache.org 
Sent: Tuesday, April 29, 2014 10:20:40 AM 
Subject: Writing data from iterators 

Bit of a tangent... This came up earlier in the text indexing thread and 
below, and is something I've seen come up a couple of other times. 

What would it take to make it so something tabletserver-side could write to 
accumulo (in an "acceptable way")? Either be it an iterator/constraint or 
something new. 

-d 


On Tue, Apr 29, 2014 at 9:59 AM, Eric Newton <eric.newton@gmail.com> wrote: 

> I have taken a quick look at phoenix. It's baked into HBase-specific 
> features pretty hard. 
> 
> It uses coprocessors to do things like create index entries. This is a 
> common enough idiom in the HBase community, but not something we've 
> supported in Accumulo. In general, you do not want an accumulo Iterator or 
> Constraint generating data for other tables. 
> 
> However, a more sophisticated Percolator type implementation ( 
> https://github.com/keith-turner/Accismus) could support index generation 
> and query transactions. 
> 
> We could probably re-use a lot of it, but it's not going to be as simple as 
> changing the classes that talk to the database back-end. 
> 
> -Eric 
> 
> 
> On Tue, Apr 29, 2014 at 9:21 AM, Kepner, Jeremy - 0553 - MITLL < 
> kepner@ll.mit.edu> wrote: 
> 
> > Hi James, 
> > Can you explain how the SQL layer to HBase works? 
> > Regards. -Jeremy 
> > 
> > On Apr 29, 2014, at 1:32 AM, James Taylor <jamestaylor@apache.org> 
> > wrote: 
> > 
> > > Hello, 
> > > Would there be any interest in developing a SQL-layer on top of 
> Accumulo? 
> > > I'm part of the Apache Phoenix project and we've built a similar system 
> > on 
> > > top of HBase. I wanted to see if there'd be interest on your end at 
> > working 
> > > with us to generalizing our client and provide in a server that would 
> do 
> > > Accumulo-specific push down in support of a SQL layer. I suspect 
> there's 
> > > enough similarity between HBase and Accumulo that this would be 
> feasible. 
> > > Thanks, 
> > > James 
> > 
> > 
> 



-- 

Donald Miner 
Chief Technology Officer 
ClearEdge IT Solutions, LLC 
Cell: 443 799 7807 
www.clearedgeit.com 


Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message