You can get more speed by pushing logic into the DB and putting relational and fundamental bits in the DB makes then easier to isolate and secure, but your application becomes bound to the DB and logic in the DB tends to be more obscure and harder to debug. From a purely design aesthetic position it's a bad idea, but in most situations, the practical benefits outweigh the problems.

Can't say that I have any particular references for this point of view though.

Jay