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RE: Re: `svn log -v' time inefficiencies

From: Bill Tutt <rassilon_at_lyra.org>
Date: 2002-06-13 23:00:07 CEST

> From: Karl Fogel [mailto:kfogel@newton.ch.collab.net]
>
> cmpilato@collab.net writes:
> > To address this, Karl proposed the idea of storing the changed paths
> > as a revision property. That is, as a person changes things in a
txn,
> > we will track the changed paths as a transaction property. Then, at
> > commit time (where we already initialize the revision properties by
> > copying the transaction's properties) those would become revision
> > properties. Wah-lah, constant-time answers to "What changed in this
> > revision?"
> >

I could have sworn we talked about this ages and ages ago..... I'm all
+1 on the idea.

> > It seems kinda Band-aid(tm)-ish to me, but only because of the
> > redundancy aspect (we *can* derive that information, it just takes
> > time proportional to the size of the changes made to any given
> > revision). But if a Band-aid(tm) is what we need, then it's what we
> > need.
>

Alan adequately explained the data modeling concept of denormalizing
data. This is indeed what we're doing here. It's mucho goodness.

Just as a little side note wrt denormalization:
In SQL datastores every additional index you add is really denormalized
data, it's just very useful denormalized data.

Intelligently applied denormalization is a very good thing.

FYI,
Bill

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Received on Thu Jun 13 23:00:49 2002

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