[psaintla]

Around 2005 I worked for a fairly large company that did exactly what you're suggesting with Postgresql and it was a complete disaster. Have you ever tried implementing sharding with all of your business logic in stored procedures? Have you ever tried hiring people who understand pl/sql and WANT to work with it? I have done both and it is a nightmare, once you get to the point of having to shard data you end up in one of two places:

1.) The sprocs become insanely complex because they have to be shard aware.

2.) You slowly start moving more of your code that was in sprocs to your application so now you've got two problems.

As for hiring, put out an ad for an engineer with pl/sql knowledge better yet put out an ad for someone who wants to learn and use pl/sql. Good luck finding enough of those people to get any significant work done.