Return-Path: Delivered-To: apmail-couchdb-user-archive@www.apache.org Received: (qmail 10427 invoked from network); 21 Sep 2010 17:24:17 -0000 Received: from unknown (HELO mail.apache.org) (140.211.11.3) by 140.211.11.9 with SMTP; 21 Sep 2010 17:24:17 -0000 Received: (qmail 87564 invoked by uid 500); 21 Sep 2010 17:24:16 -0000 Delivered-To: apmail-couchdb-user-archive@couchdb.apache.org Received: (qmail 87515 invoked by uid 500); 21 Sep 2010 17:24:15 -0000 Mailing-List: contact user-help@couchdb.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@couchdb.apache.org Delivered-To: mailing list user@couchdb.apache.org Received: (qmail 87504 invoked by uid 99); 21 Sep 2010 17:24:15 -0000 Received: from Unknown (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 21 Sep 2010 17:24:15 +0000 X-ASF-Spam-Status: No, hits=0.0 required=10.0 tests=FREEMAIL_FROM,RCVD_IN_DNSWL_NONE,SPF_PASS,T_TO_NO_BRKTS_FREEMAIL X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: domain of randall.leeds@gmail.com designates 209.85.161.52 as permitted sender) Received: from [209.85.161.52] (HELO mail-fx0-f52.google.com) (209.85.161.52) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 21 Sep 2010 17:23:53 +0000 Received: by fxm14 with SMTP id 14so1249923fxm.11 for ; Tue, 21 Sep 2010 10:23:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:in-reply-to :references:date:message-id:subject:from:to:content-type; bh=hz5bQOZ96atZftaYjeFOOWa38aFVzkkmxDup0Xj6eE4=; b=s0Qf+YF0upVpxfLkQoxl/RbgW4YLV5abE1SDAC3ovPogld3+AjBdxcQihiRWqGz8un NBMVL25t5zROfatVP9F/ytH7Hl/omJOQuQgAbJl0E+9qcthaZ2nnTZ4NuetLrnxxNqrI s0E/0hwXObRBwckvLpOMSwoN6jDJYXN/h0X6I= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=p9S/SY1UVIBYVXBytQUj1mURSUyqfFpkKo4lL6VEIG/YoDAhM5iDGuC7L8zAoRqv+n 8MjZhadgJhGsYox66Xxp/IiUYVOm9UQALlwttAHdqGJIqSIHuLzKN/ucoiVOJuc1P0Rp r9fAb4TnjOXYEvn/UG6E2rerJWdG4dJHNmyaA= MIME-Version: 1.0 Received: by 10.223.112.206 with SMTP id x14mr6570015fap.89.1285089813617; Tue, 21 Sep 2010 10:23:33 -0700 (PDT) Received: by 10.223.111.141 with HTTP; Tue, 21 Sep 2010 10:23:33 -0700 (PDT) In-Reply-To: References: Date: Tue, 21 Sep 2010 19:23:33 +0200 Message-ID: Subject: Re: distributed map-reduce queries From: Randall Leeds To: user@couchdb.apache.org Content-Type: text/plain; charset=UTF-8 X-Virus-Checked: Checked by ClamAV on apache.org On Tue, Sep 21, 2010 at 18:19, Christopher Bare wrote: > > I only vaguely understand the incremental indexing aspect of Couch, > and welcome any comments about other differences between Couch's > map-reduce and other forms; biting or not. There's lots of cool > engineering to explore. This means that the index is persistent. A view is only calculated once even if you query it multiple times. When new documents are added those are added to the index without recalculating the entire M/R. This also means that your M/R code must be deterministic and cannot involve query-time user variables. -Randall