On 11/12/2007, Simon Riggs <[EMAIL PROTECTED]> wrote: > > Attach > ------ > > Writing tables on one system and then moving that data to other systems > is fairly common. If we supported read-only tables then you might > consider how you would publish new versions to people. > > For now, we just want to consider how we will upgrade from one release > to another without needing to unload and reload potentially many > Terabytes of data. We can't delete the old data until the new data is > successfully loaded, so we will have a huge temporary storage cost. This > could go very slowly if we use cheaper storage, plus reloading the data > means we have to re-freeze it again also. > > So we need a way of attaching the old tables to the new database. We > might call this binary upgrade, or we might be slightly less ambitious > and talk about just moving the old read-only data. That's all I want to > do at this stage. > > I'm mentioning this here now to see what comes out in debate, and what > others are planning to work on in this area. > > This sounds like allowing new versions to read old versions file structure, Probably I guess on a tablespace by table space basis
Another advantage might be to be able to load an old pitr backup in a new version across major versions. But I'm not sure that would work. Maybe we need a command to upgrade a tablespace to a new versions file format? Need to be careful we don't stunt future progress by fixing file format much. Peter Childs
