openstack team mailing list archive

[Soren Hansen <soren@xxxxxxxxxxx>]

2011/11/29 Jay Pipes <jaypipes@xxxxxxxxx>:
> There's a very good reason this hasn't happened so far: handling
> highly relational datasets with a non-relational data store is a bad
> idea. In fact, I seem to remember that is exactly how Nova's data
> store started out life (*cough* Redis *cough*)

To be fair, we're only barely making use of this in our DB
implementation. I don't think we do any foreign key checking at all,
and deletes (because we don't actually delete anything, we just mark
it as deleted) don't cascade, so there are all sort of ways in which
our data store could be inconsistent.

Besides, we don't really use transactions. I could easily read the
same data from two separate nodes, make different (irreconcilable)
changes on both nodes, and write them back, and the last one to write
simply wins.

In short, it seems to me we're not really getting much out of having a
relational data store?

-- 
Soren Hansen        | http://linux2go.dk/
Ubuntu Developer    | http://www.ubuntu.com/
OpenStack Developer | http://www.openstack.org/