Improving functions
So far, you have seen how to write basic functions and triggers in various languages. Of course, many more languages are supported. Some of the most prominent ones are PL/R (R is a powerful statistics package) and PL/v8 (which is based on the Google JavaScript engine). However, those languages are beyond the scope of this chapter (regardless of their usefulness).
In this section, we will focus on improving the performance of a function. There are a few ways by which we can speed up processing:
- Reducing the number of function calls
- Using cached plans
- Giving hints to the optimizer
In this section, all three of these topics will be discussed. Let’s get started with reducing the number of function calls and see how this can be done.
Reducing the number of function calls
In many cases, performance is bad because functions are called way too often. In my opinion—and I cannot stress this point enough—calling things too...