----- Original Message ----- > From: "Johannes Erdfelt" <johan...@erdfelt.com> > To: openstack@lists.launchpad.net > Sent: Friday, April 27, 2012 12:13:47 PM > Subject: Re: [Openstack] database migration cleanup > > On Fri, Apr 27, 2012, Dan Prince <dpri...@redhat.com> wrote: > > > Mirations don't appear to be particularly slow right now, and it > > > doesn't > > > appear that merging migrations will make them significantly > > > faster. > > > > > > What exactly is the benefit of doing this? > > > > Speed wasn't the primary motivation here I suppose. Do we really > > want > > to continue to maintain 100+ migrations in our codebase over the > > lifetime of the project? As we add more and more to our > > pep8/hacking > > tools this could become an annoying burden right? > > Has that been a problem? > > I'm not sure I see where pep8/hacking changes would require changes > to > the unmerged migrations but the merged migrations wouldn't require > them. > Wouldn't that affect either?
The primary benefit here is it is simply less code to maintain: The old migrations scripts for Essex are around 6200 lines of code. The new compacted migration for Essex is around 950 lines of code. > > Looking at the logs for the migrations most of the changes (outside > of > PEP8 changes) appear to be sqlalchemy related changes, which will > exist > regardless if they are merged or not as well. > > > I mean why require end users to run migrations that add and drop > > the > > same table repeatedly? > > It's hard to just grep for which migrations drop a table/column added > in > a previous migration. Did you see how many are like that when you > merged > all of the migrations together? > > > I'm not sure I understand? Git still has the source code for the > > old > > migrations. All you'd need to do is checkout an old version of > > master > > or look at the stable/essex, stable/diablo branches right? > > True, you would just need to go out of your way to look at the > history > instead. > > I guess it's a matter of pros vs cons. Right now, I'd prefer to not > merge them simply because I haven't seen what the benefit is. The primary benefit here is just cleaning up our code base. If that isn't a good reason or if you'd rather keep the 82 Essex migrations in the code base for the long term please feel free to comment accordingly on the merge proposal. Dan > > JE > > > _______________________________________________ > Mailing list: https://launchpad.net/~openstack > Post to : openstack@lists.launchpad.net > Unsubscribe : https://launchpad.net/~openstack > More help : https://help.launchpad.net/ListHelp > _______________________________________________ Mailing list: https://launchpad.net/~openstack Post to : openstack@lists.launchpad.net Unsubscribe : https://launchpad.net/~openstack More help : https://help.launchpad.net/ListHelp
