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Date: Thu, 29 Sep 2016 01:33:42 -0400
From: Josh Elser <josh.elser@gmail.com>
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To: user@accumulo.apache.org
Subject: Re: Indexing Column Values in Accumulo
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archived-at: Thu, 29 Sep 2016 05:34:00 -0000

Hi Yamini,

You're right that a filter would have to exhaustively search a table to 
find all rows that contain a certain family and qualifier. If you 
explicitly know the rows that you want to search, this is a fast operation.

Have you considered creating an inverted index? This would be a table 
that you have to maintain on your own. Accumulo does not provide 
automatic index generation.

- Josh

Yamini Joshi wrote:
> Hello everyone
>
> Is there a way to easily index column fields for efficient lookups in
> Accumulo? My use case is to select the records containing a certain
> column family and column qualifier from among a set of column
> qualifiers(reverse lookup). Although this could be done using a custom
> filter, I'm looking for an optimal solution (since filter might scan the
> entire database).
>
> Best regards,
> Yamini Joshi