On Wed, Aug 27, 2014 at 10:13 AM, Bruce Momjian <br...@momjian.us> wrote: > On Wed, Aug 27, 2014 at 09:54:11AM -0400, Robert Haas wrote: >> Having said that, there are obviously advantages for our users if we >> don't get too crazy about requiring that. I've used products in the >> past where to get from version 3 to version 11 you have to upgrade >> from 3 to 5, then 5 to 7, then 7 to 9, and then 9 to 11. That's >> somewhat understandable from the vendor's point of view, but it's not >> a lot of fun, and I think we should definitely avoid imposing those >> kinds of requirements on our users. >> >> What we're talking about here is much milder than that. For the >> pg_upgrade case, you can upgrade from 8.3 to any of 8.4, 9.0, 9.1, >> 9.2, 9.3, and 9.4. You only need to do a two-step upgrade if you want >> to leapfrog more than 6 major release versions. That seems like a >> wide-enough window that it shouldn't inconvenience many people. For >> the pg_dump case, you can upgrade from 7.2 or 7.3 to 7.4, 8.0, 8.1, >> 8.2, 8.3, 8.4, 9.0, 9.1, 9.2, 9.3, or 9.4; that is, 11 or 12 major >> releases. The number of people who want to skip more than a dozen >> releases in a single upgrade should be very small, and we might >> council those people that they'd be better off with a step-wise >> upgrade for other reasons - like the application-level compatibility >> breaks we've made over the years - anyway. > > Two things --- first, removing 8.3 support in pg_upgrade allowed me to > remove lots of dead code, so it was a win. Second, I think you need to > look at the time span from old to new versions to understand if a > double-step release is reasonable. If that 3-5-7-9 release step spans > two years, it is too short --- if it spans 15 years, it is probably fine > as few people would wait 15 years to upgrade.
Right, I agree with all of that and was not intending to dispute any of it. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
