Return-Path: X-Original-To: apmail-cassandra-user-archive@www.apache.org Delivered-To: apmail-cassandra-user-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id F0D23C526 for ; Tue, 10 Jul 2012 09:11:40 +0000 (UTC) Received: (qmail 76751 invoked by uid 500); 10 Jul 2012 09:11:38 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 76713 invoked by uid 500); 10 Jul 2012 09:11:38 -0000 Mailing-List: contact user-help@cassandra.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@cassandra.apache.org Delivered-To: mailing list user@cassandra.apache.org Received: (qmail 76389 invoked by uid 99); 10 Jul 2012 09:11:37 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 10 Jul 2012 09:11:37 +0000 X-ASF-Spam-Status: No, hits=2.2 required=5.0 tests=FSL_RCVD_USER,HTML_MESSAGE,RCVD_IN_DNSWL_NONE,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (athena.apache.org: local policy) Received: from [208.113.200.5] (HELO homiemail-a83.g.dreamhost.com) (208.113.200.5) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 10 Jul 2012 09:11:32 +0000 Received: from homiemail-a83.g.dreamhost.com (localhost [127.0.0.1]) by homiemail-a83.g.dreamhost.com (Postfix) with ESMTP id AB2055E063 for ; Tue, 10 Jul 2012 02:11:10 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; c=nofws; d=thelastpickle.com; h=from :mime-version:content-type:subject:date:in-reply-to:to :references:message-id; q=dns; s=thelastpickle.com; b=Z1IfDYrRIX H0CRwS0lsGCBaRUcqh5bvcLTQqYivAb7MYuBgoUtfoc10oLrGZ9WQ6U8XCjuWNQc h4FE8uY4iUqb+i7P+nQRbGkxwlJygqMRkzM2rL60wdG3oZ6tzLFiKhvJ4F1ul30z rcMLU+cwknD9E0x3ccsC97CexQNuEshvw= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=thelastpickle.com; h=from :mime-version:content-type:subject:date:in-reply-to:to :references:message-id; s=thelastpickle.com; bh=FS9tnWl/kuoP48Ns n8sxajJgTvs=; b=Q6F6kzEtztFRuThdCubrjQe5PFgU/ifN6huugvVp7erm/cp+ 4DT7O5qQGcA14dWgfilcTYUbgCNDWg5AG59RlYKlplKz3Qj7GkUJt5XRQhUHXyrB kVKAvwBLfIN9kWNXFU33IEz19KpJpAlG+3BAOoxquGcg3Iy67SAAyR4AX5k= Received: from [172.16.1.4] (unknown [203.86.207.101]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) (Authenticated sender: aaron@thelastpickle.com) by homiemail-a83.g.dreamhost.com (Postfix) with ESMTPSA id D0D825E060 for ; Tue, 10 Jul 2012 02:11:09 -0700 (PDT) From: aaron morton Mime-Version: 1.0 (Apple Message framework v1278) Content-Type: multipart/alternative; boundary="Apple-Mail=_19955565-ED3D-4581-9634-13BC6D1EB241" Subject: Re: Effect of rangequeries with RandomPartitioner Date: Tue, 10 Jul 2012 21:11:03 +1200 In-Reply-To: To: user@cassandra.apache.org References: <94A5F3E1-1DD6-4A6A-8D17-D7BFD71F100B@thelastpickle.com> Message-Id: <32A17BEA-4E93-4427-8615-87B1621E4A1E@thelastpickle.com> X-Mailer: Apple Mail (2.1278) X-Virus-Checked: Checked by ClamAV on apache.org --Apple-Mail=_19955565-ED3D-4581-9634-13BC6D1EB241 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=iso-8859-1 Index files map keys (not tokens) to offsets in the data file. A range scan uses the index file to seek to the start position in the = data file and then does a partial scan of the data file.=20 Cheers ----------------- Aaron Morton Freelance Developer @aaronmorton http://www.thelastpickle.com On 9/07/2012, at 7:24 PM, prasenjit mukherjee wrote: > Thanks for the response. Further questions inline.. >=20 > On Mon, Jul 9, 2012 at 11:50 AM, samal wrote: >>> 1. With RandomPartitioner, on a given node, are the keys sorted by >>> their hash_values or original/unhashed keys ? >>=20 >> hash value, >=20 > 1. Based on the second answer in > = http://stackoverflow.com/questions/2359175/cassandra-file-structure-how-ar= e-the-files-used > it seems that the index-file ( for a given ssTable ) contains the > row-key ( and not the hash_keys ). Or may be I am missing something. >=20 > 2. Do the "keys" in Index-file ( ref > http://hi.csdn.net/attachment/201111/28/0_1322461982l3D8.gif ) > actually contain : hash(row_key)+row_key or something like that ? > Otherwise you need a separate mapping info from hash_bucket -> rows > for reading. >=20 > -Thanks, > Prasenjit --Apple-Mail=_19955565-ED3D-4581-9634-13BC6D1EB241 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=iso-8859-1
http://www.thelastpickle.com
On 9/07/2012, at 7:24 PM, prasenjit mukherjee = wrote:

Thanks for the response. Further questions = inline..

On Mon, Jul 9, 2012 at 11:50 AM, samal <samalgorai@gmail.com> = wrote:
1. With = RandomPartitioner, on a given node, are the keys  sorted = by
their hash_values or original/unhashed keys =  ?

hash = value,

1. Based on the second answer in
http://stackoverflow.com/questions/2359175/cassa= ndra-file-structure-how-are-the-files-used
it seems that the = index-file ( for a given ssTable ) contains the
row-key ( and not the = hash_keys ).  Or may be I am missing something.

2. Do the = "keys" in  Index-file ( = ref
http://hi.csdn.net/attachment/201111/28/0_1322461982l3D8.gif = )
actually contain : hash(row_key)+row_key or something like that = ?
Otherwise you need a separate mapping info from hash_bucket -> = rows
for = reading.

-Thanks,
Prasenjit

= --Apple-Mail=_19955565-ED3D-4581-9634-13BC6D1EB241--