Mailing-List: contact issues-help@hbase.apache.org; run by ezmlm
Precedence: bulk
Message-ID: <23718528.455271279553270550.JavaMail.jira@thor>
Date: Mon, 19 Jul 2010 11:27:50 -0400 (EDT)
From: "stack (JIRA)" <jira@apache.org>
To: issues@hbase.apache.org
Subject: [jira] Commented: (HBASE-32) [hbase] Add row count estimator
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit


    [ https://issues.apache.org/jira/browse/HBASE-32?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12889889#action_12889889 ] 

stack commented on HBASE-32:
----------------------------

@Duane Hey. Thanks for the offer of help.  Appreciated.  You might want to look at coprocesors -- hbase-2000 -- and minitables, HBASE-2571, in particular.  I believe current thinking is that aggregations, sums, etc., would be done as code loaded as coprocessors.  

> [hbase] Add row count estimator
> -------------------------------
>
>                 Key: HBASE-32
>                 URL: https://issues.apache.org/jira/browse/HBASE-32
>             Project: HBase
>          Issue Type: New Feature
>          Components: client
>            Reporter: stack
>            Priority: Minor
>         Attachments: 2291_v01.patch, Keying.java
>
>
> Internally we have a little tool that will do a rough estimate of how many rows there are in a dataHbase.  It keeps getting larger and larger partitions running scanners until it turns up > N occupied rows.  Once it has a number > N, it multiples by the partition size to get an approximate row count.  
> This issue is about generalizing this feature so it could sit in the general hbase install.  It would look something like:
> {code}
> long getApproximateRowCount(final Text startRow, final Text endRow, final long minimumCountPerPartition, final long maximumPartitionSize)
> {code}
> Larger minimumCountPerPartition and maximumPartitionSize values would make the count more accurate but would mean the method ran longer.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.