Re: Making metadata storage SQL-driven

[Manuel Amador <rudd-o amautacorp com>]

Jamie, this argument sounded way like "yes, but this sportscar has a
limited-slip differential" when you need a 4x4 vehicle to cross a huge
mud puddle.

Yes, MySQL embedded may be wonderful.  But using it will leave many,
many, many requirements unimplemented, and will complicate
interoperability.  Same goes for using DBUS to shield a MySQL-based
metadata library.  Doing this will make stuff much harder to script.

I for sure would like to login as rudd-o on /dev/tty1 and be able to
find files by metadata with /usr/bin/find, or lsattr on a file.
Please tell me:

- how I'll do this if metadata data is in a MySQL store, abstracted by
DBUS
- if you solve this, how much harder will it be to adapt /usr/bin/find
to your solution... if you don't use EAs.

ATM I could perhaps use beagle-query.  But I want /usr/bin/find, not
slocate.  Locality and greppability of metadata matters.

> thats true for some DBs but not all.
> 
> For instance the embedded mysql needs no set up and it will work out of 
> the box (its just a shared library) so installation and setup is a 
> non-issue. It has no locking issues as the INNODB stuff in mysql is 
> multi generational so readers and writers dont block each other and its 
> totally safe as a write generates a new copy of a record and the commit 
> on it is atomic so even of there's a power failure during a write 
> corruption will not occur to anything committed.
> 
> With a dbus interface all access can be both sync or async so I dont see 
> a problem there.
> 
> Also you need multiple tables to store or use RDF and contextual data 
> which is highly relational in nature and cannot be efficiently stored in 
> a single key value table.
> 
> My plan is to have a gnome-vfs driver to it so you can use nautilus to 
> contextual browse your file metadata so you could for example enter a 
> folder called "emails from bob" which would show corresponding emails 
> etc. Contextual data is very hierarchical so this would be a good case 
> for it.
> 
> -- 
> Mr Jamie McCracken
> http://www.advogato.org/person/jamiemcc/
-- 
Manuel Amador                   <rudd-o amautacorp com>
http://www.amautacorp.com/            +593 (4) 220-7010