Using Pgsql for everything shows you've been drinking the internet kool-aid. And that site is like a creepy shrine saying pgsql is the alpha and omega.

Like any tool, it works until it doesn't. And when it doesn't it takes a herculean effort to unwind it.

I looked at the first entry and yeah, just say no to moving your business logic into your database. Because change happens...and don't you want that happening in something more plastic than your RDBMS? But it's a great way to bind your solution to Postgres forever.

As an aside, I've used oracle, sybase, informix, mysql, postgresql, rdb, db2, mssql, and a few more that I can't remember. And the idea that pgsql is always the answer is the wrong answer to probably the wrong question.