+1 to giving flyway a try. I have used it before and it *mostly* worked. There were a few hiccups occasionally when it couldn’t properly recognize the DB drift and failed to apply the update but that was entirely incremental build-related problem (flyway was integrated into the build process).
What flyway does not support is version rollbacks. It's not applicable to this particular change but I am sure there will be changes where we'd need to move data as part of DB upgrade. If we then decide to rollback due to an unforeseen problem we would have to have reverse migration script(s). Not impossible but something to keep in mind. On Wed, Mar 23, 2016 at 4:41 PM, Florian Pfeiffer <florian.pfeif...@gutefrage.net> wrote: > We're using flyway for our services, and from an ops perspective I'm quite > happy with it. On test it's allowed to apply the migrations > automatically... on prod we're doing it manually after reviewing. No > problems so far. > I can't really tell anything from the dev side, beside that I haven't > heard them complaining about it (and normally they are complaining quite > fast ;) )... > > Another thing that's similar to flyway is http://www.liquibase.org/ but for > that I have zero experience. > > Flo > > > On 23 March 2016 at 22:41, Joshua Cohen <jco...@apache.org> wrote: > >> If we go with option 2 (which I'm leaning towards as well), does anyone >> have thoughts on using (or experience with) something like Flyway: >> https://flywaydb.org/ rather than implementing from scratch? >> >> On Wed, Mar 23, 2016 at 3:29 PM, John Sirois <jsir...@apache.org> wrote: >> >> > On Wed, Mar 23, 2016 at 2:21 PM, Joshua Cohen <jco...@apache.org> wrote: >> > >> > > Hi Aurorans, >> > > >> > > As you may have seen ( >> https://issues.apache.org/jira/browse/AURORA-1648 >> > ), >> > > we ran into an issue when upgrading a cluster that uses dbScripts in >> > > snapshots. To restate the problem from the ticket, when the scheduler >> > > starts up it creates the H2 database from schema.sql which contains >> newly >> > > added (or changed) tables. If the dbScript exists in the snapshot, it >> > then >> > > drops all tables and runs the script which re-creates the database in >> the >> > > form it was previously in and repopulates all the data. At this point, >> > if a >> > > table was added that was not in the snapshot, that table is lost. >> > > >> > > The solution here is to be run a migration after restoring the >> database, >> > my >> > > question is what level of complexity do we want for migrations. I see >> two >> > > possible options: >> > > >> > > >> > > 1. The relatively simple approach where we have a single >> migration.sql >> > > alongside schema.sql which contains any changes to run against the >> > > database. After restoring the db from a dbScript in the snapshot, we >> > > would >> > > run this script. On release boundaries(?), we clear the script out. >> > The >> > > main caveat here is that the ddl statements in this script must be >> > > idempotent since they would potentially be run multiple times. >> Another >> > > issue is this would make it more complicated to jump over versions >> > > (upgrading from v0.12.0 to v0.14.0 means you might miss a migration >> > that >> > > only existed in the 0.13.0 release). >> > > 2. A slightly more involved approach would be to track the schema >> > > version in the database itself. Instead of having a single >> > migration.sql >> > > script that contains all migrations, we could instead have >> > > migrations/001.sql, migrations/002.sql, etc. We'd add a new table to >> > the >> > > database to track which migrations have been run. After restoring >> via >> > > dbScript, we'd check the table and run any migrations necessary (or >> > all >> > > of >> > > the table does not exist). >> > > >> > > Thoughts on these options? >> > > >> > >> > I have used 2 a few times in the past and my take is it only more complex >> > in 1 fixed piece of (java) code that can be well unit tested. The sql >> > scripts are easier to read and write and reason about for devs and >> > operators alike. >> > >> > >> > > >> > > Anyone have any alternatives? >> > > >> > > Cheers, >> > > >> > > Joshua >> > > >> > >> > > > > -- > Head of Data & Infrastructure > florian.pfeif...@gutefrage.net > +49-89-515146-173 > > gutefrage.net GmbH > Ein Unternehmen der Verlagsgruppe Georg von Holtzbrinck > Erika-Mann-Str 23 > 80636 München
