Re: Expert: PL/SQL procs vs Queries

I can't answer the question authoritatively, but offer the following observations:

(1) creating the common functions is a good programming practice

      regardless of the possible performance penalty.  If the business
      rule is going to be used over and over in many contexts, it is
always
      a good idea to make sure that the same question receives the 
      same answer whenever it is asked.  It also greatly simplifies the
      problem of modifying the rule:  you only have to change it in one 
      place.  My advice is that, unless the MEASURED performance
      penalty is huge, go with the PL/SQL.  This leads me to observation



(2) My experience with Oracle 7 is that there is no a priori way to 


      predict the performance of a query (unless the query contains
      cartesian product type joins).  The only accurate way to determine 
      the performance of a query is to measure it.  Often the results
      will be quite surprising.