From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 15 Aug 2012 19:33:27 +0200 From: tlaronde@polynum.com To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> Message-ID: <20120815173327.GA424@polynum.com> References: <20120803171847.GA2720@polynum.com> <501D12A1.1060906@yahoo.fr> <20120804152016.GB433@polynum.com> <20120805173639.GA395@polynum.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.3i Subject: Re: [9fans] Multi-dimensional filesystem Topicbox-Message-UUID: a9adc6e8-ead7-11e9-9d60-3106f5b1d025 On Wed, Aug 15, 2012 at 07:04:28PM +0300, Eugene Gorodinsky wrote: > I'm sure I must not understand the problem fully and am confused because of > that, but how is this idea of multidimensionality different from a > relational filesystem approach such as befs ( > http://www.nobius.org/~dbg/practical-file-system-design.pdf)? One can obviously mimick what I have described with a database, fields, the relationships being built by indexing. The hierarchical (but with multiple parents as well as multiple children) is a representation of the indexing in this case. So the BeFS could---from a cursory look about the combination of database, indexing and hierachy representation---offer a solution, except that the multiple parents, is not there (this could be, as well as with other systems, be done with .+ and .- presentation). The main differences from what I have in mind are: 1) There is no general relational database concept: the relationships of the "records" (files, that can have both a text content [the definition in my example] and be a directory node) is exclusively isomorphic to coordinates: (i, j, k, ...). 2) There is no constraint in the size of the "fields": the dimension can grow with time (no given dimensions coordinates being, by convention, equal to 0 to reach the actual dimension) ; there is no limit (except implementation one) for the size of an enumeration. 3) The hierarchy is the user interface, to view and to add the data: a new file (record) is added by placing it in the hierarchy; while in a relational database, the indexing is deduced from the actual records; here, so to say, the data is entered through the indexing. 4) And the problem was also thought through 9P: is there something in 9P that would prevent, at least theoritically, such a view of data to be presented? With the convention of ".+" and ".-", my answer is no: 9P has no hardcoded knowledge of ".." if I'm not mistaken. -- Thierry Laronde http://www.kergis.com/ Key fingerprint = 0FF7 E906 FBAF FE95 FD89 250D 52B1 AE95 6006 F40C