What you're actually describing is the fundamental weakness of backend-specific development: move to/meet a customer who insists on an alternative backend and you lose the vendor-specific stuff you've come to rely on. I had the same discussion with JVP more than once; wonder whether the outcome will be different this time? ;-)

I don't consider ANSI-99 to be vendor-specific :)

FWIW, JVP and I had "one" discussion about MySQL, a few years ago, and at the time, he was comparatively a tad more in favor of MySQL than I was.