[rossdavidh]

Having worked on old systems that used this approach, I recall that it did have a lot of pluses. Now, for the minuses:

1) changing the language you use in a server (say, from PHP to Python) is big, but changing the language you use in your database (from SQL to anything else) is even more intimidating. If you are integrating through the database, this limitation matters more.

2) you need to have DBA's who are not only highly competent, but also have good people skills, since they will often be saying "no", or at least "not that way", and if they don't know how to do that in a constructive manner then it becomes a net productivity drain. Fortunately, where I worked that used this pattern, the DBA's had exceptional people skills as well as technical skills. This is, I am led to believe, not always the case.