From mboxrd@z Thu Jan  1 00:00:00 1970
From: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Subject: Re: Git's database structure
Date: Thu, 6 Sep 2007 13:56:36 +0100 (BST)
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Cc: Julian Phillips <julian@quantumfyre.co.uk>,
	Andreas Ericsson <ae@op5.se>, Theodore Tso <tytso@mit.edu>,
	Junio C Hamano <gitster@pobox.com>,
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To: Jon Smirl <jonsmirl@gmail.com>
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Hi,

On Wed, 5 Sep 2007, Jon Smirl wrote:

> On 9/5/07, Julian Phillips <julian@quantumfyre.co.uk> wrote:
> > On Wed, 5 Sep 2007, Jon Smirl wrote:
> >
> > >> Ah, there we go. A use-case at last :)
> >
> > But not a brilliant one.  You sign off on commits not blobs.  So you 
> > go from the sign-off to paths, then to blobs.  There is no need to go 
> > from blob to path unless you deliberately introduce such a need.
> 
> Use blame for an example. Blame has to crawl every commit to see if it 
> touched the file. It keeps doing this until it figures out the last 
> author for every line in the file. Worse case blame has to crawl every 
> commit in the data store.

But you can add _yet another_ index to it, which can be generated on the 
fly, so that Git only has to generate the information once, and then reuse 
it later.  As a benefit of this method, the underlying well-tested 
structure needs no change at all.

BTW could you please, please, please cut the quoted message that you are 
_not_ responding to?  It really _wastes_ my time.

Ciao,
Dscho