[Biojava-l] BioSQL observations

[Matthew Pocock]

Keith James wrote:

> On the schema itself, was there any discussion on being able to track
> changes to Features? I'm thinking of situations where the a number of
> people are applying annotation to a genome and want to know "when was
> this Feature last modified?"

If editing is needed, then you realy need to maintain version 
information to allow rollbacks, resolution of clashes between different 
edits, keeping views current and the rest. My first stab would be on the 
unique key for features being an (ID,version) tuple where versions are 
monotopicaly increasing integers, or a timestamp. (Do we need branching 
ala CVS?) Things should link through tables by ID, but the fetch query 
should usualy select id,max(version) - we would need nested queries to 
do this efficiently. Alternatively, you could have each new feature 
(including all features made by editing old features) have unique IDs, 
and store the edit history in a seperate edits table (things like, 
feature A was modified by user X to become feature B). Would these 
aproaches kill performance? Is this another case where the data model 
needs to be specified by something more loosely bound than object 
models, adaptor code or table definitions? My brain is melting.

> Keith
> 

Matthew