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From: Jens Alfke <jens@couchbase.com>
To: "user@couchdb.apache.org" <user@couchdb.apache.org>
Date: Thu, 14 Nov 2013 15:56:01 -0800
Subject: Re: show/list
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On Nov 14, 2013, at 2:19 PM, Benoit Chesneau <bchesneau@gmail.com> wrote:

> I have examples in prod that shows that not anyone is sharing the same
> opinion as you ;) There are plenty of example where lists and shows can b=
e
> used.

I=92m sure there are. They=92re just not particularly useful when the datab=
ase is embedded inside the app. The kind of postprocessing list/show functi=
ons do is useful when the client and server are widely separated since it s=
aves you a lot of round-trips and can massage data into the form a client e=
xpects. That=92s not an issue when the app and db live within the same proc=
ess.

> Where
> the use of lists and shows, the fact that you can replicate them (which i=
s
> possible when you use ios and android outside the app store in entreprise=
s
> or private events) is a huge advantage.

You can implement list/show functions outside the database. You can even pu=
t them in a library function in your CouchApp and replicate them that way. =
They=92re just handy utilities, not actual database functionality.

> Why some person are using
> SQL? Because they can query the data. Why woud you like to have shows and
> lists or any feature like this? Because you eventually build your own way
> to query your data.

I=92m not saying the ability to postprocess query results isn=92t useful. I=
=92m just saying that list and show functions are a hacky way to do it. The=
y remind me of old CGI programs that painstakingly assembled HTML by string=
 concatenation, instead of using something like a template language. And th=
e fact that they=92re manipulating the results in text form makes them inef=
ficient and prone to errors. Ideally you=92d transform the data directly as=
 objects instead of having to convert them into text that then gets parsed =
by something else.

=97Jens=