Do not try to run migrations in transactions on databases that do not support transactional ddl

[Nthalk]

Previously, in ticket #655, PostgresSQL was given special java api support to do things like vacuum that do not play nicely within transactions.

I currently have a script that renames a lot of constraints in Oracle, and apparently, there is some hidden limit to that within a transaction that causes the script to fault, yet run fine without a wrapping transaction.

However, #655 introduced supportsDdlTransactions, a good hint that perhaps, for migrating, we should not use a transaction, since an error will mean that we will most likely end up in an inconsistent state, and need other tools for rollbacks (I've been using vagrant && vagrant-snapshot).

[axelfontaine]

Interesting idea. It is not without its downsides as migrations updating reference now also lose all rollbacks abilities.

Just to be sure: have you upgraded to the very latest Oracle version and verified it occurs there too?

[Nthalk]

@axelfontaine Yes, but if the database doesn't supportsDdlTransactions there really is no reasonable assumption that migrations can even be rolled back (since most all of them can be assumed to modify structure).

Unfortunately, "Using the latest version of Oracle" is not a possibility. I've dived into their support forms, and done a bunch of research, in the end I just forked this project and am using that in my own maven repo.