Mailing-List: contact user-help@couchdb.apache.org; run by ezmlm
Precedence: bulk
Reply-To: user@couchdb.apache.org
Received-SPF: neutral (athena.apache.org: local policy)
MIME-Version: 1.0
In-Reply-To: <003240CB-2132-439B-AD7D-6AFBB00DA352@apache.org>
References: 
 <CAAOi-OFMhQ0X3iEUC6T0fSdwJLV20Huj4tnJZBSfZ5Q5TtEx7g@mail.gmail.com>
 <CAN-3CBK4OQ5jJDa3ojfxkt=nN0OVpX8JnFUp21-AkgJzLTtN5g@mail.gmail.com>
 <CAAOi-OFWeYtZbLfLbsUV9Egk3j6kFtVa2t9urZu95KH3buLJdw@mail.gmail.com>
 <CAMiZLn07ru9fUgxsmtCsT2rG8ShfRrD=1bpLRN-f1YGG8athTA@mail.gmail.com>
 <CAAOi-OGEvWZrEkDyrxr1W0FKmA=Feso=smesQYU9_joARtSiqQ@mail.gmail.com>
 <CAN-3CBK3SCx7Y5K1oEC+XfzgY2B+-9_0c90m6npM9GkE_myu0g@mail.gmail.com>
 <003240CB-2132-439B-AD7D-6AFBB00DA352@apache.org>
From: Daniel Gonzalez <gonvaled@gonvaled.com>
Date: Fri, 16 Mar 2012 15:41:24 +0100
Message-ID: 
 <CAAOi-OHiVWDuAM4DUjd1q7R7voNmC5Y7uCPziC8=1DHsAU27TA@mail.gmail.com>
Subject: Re: Size of couchdb documents
To: user@couchdb.apache.org
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable

>
> If memory serves the database's by_id tree uses Erlang term sorting for c=
ollation instead of ICU. =A0ICU is of course the default collation option f=
or MR views. =A0Regards,
>
> Adam


That is interesting. I will try to confirm that, because that would
mean that the dictionary that I am using now:

"-@0123456789aAbBcCdDeEfFgGhHiIjJkKlLmMnNoOpPqQrRsStTuUvVwWxXyYzZ"

which is ICU ordered, would not be optimal for the doc_ids. Can you
tell me what would an "Erlang term order" base64 dictionary look like?

Anyway, I am curious: I understand that the size of doc_id is going to
have big impact in performance and size of the database, since the
doc_id is going to be present in a lot of internal structures. What I
do not fully understand is why *ordering* of doc_ids when inserting
documents in the database is going to have any effect in insert speed,
or view generation. In my naive view of couchdb, the documents are
just written to a big file system file as they are POSTed to couchdb,
in the order that they arrive. How would the doc_id order affect this
process?