This is a great way to tell everyone you've never had to do this type of migration.
Oracle's got a lot of nasty things going for it, for sure. But there's a reason people still use it: part of it is vendor lock-in, of course; the other is that the database is actually really nice.
Yeah I mean, I get it. Amazon spent years getting off of oracle. I'm just saying the only reason to be on oracle now is because migration is expensive. It says a lot that it's not a competitive product for new applications, and is in fact a liability.
Amazon provide multiple database offerings in their cloud, it was still a multiple year effort to move off Oracle:
Migration Complete – Amazon’s Consumer Business Just Turned off its Final Oracle Database
Today I would like to tell you about an internal database migration effort of this type that just wrapped up after several years of work.
Oh man, in theory SQL is standard - in practice, you’ll need to rewrite (or do major surgery) on nearly everything that interacts with your Oracle instance. Unless you’ve been incredibly careful, which is unlikely.
And chances are, you started using Oracle because of some enterprise software somewhere for which you don’t even have the source - so good luck.
And don’t forget, Oracle will encourage you to use all their Oracle specific stuff everywhere in their documentation. It’s a giant, idiosyncratic mess.
If you were using SQL so generically that you could easily substitute another database, you never should have been using Oracle to begin with.
I guess you could call it "vendor lock-in" to use the more advanced SQL, analytic functions, and stored procedures or you could call it "getting what you paid for."
