Section Overview

We will begin our discussion of SQL functions within this section by considering what is known as character handling functions. The sub-categories of functions for character or string handling which we will discuss in this section are:

• Formatting functions – these alter the format or output of a character string.
• ASCII codes functions – these convert a character into its ASCII code equivalent, or vice-versa.
• Pad & trim functions – these pad or trim characters at either placed at the left or right side of a character string.
• String manipulation functions – these extract, search or replace a substring within a larger character string.
• String comparison functions – these will compare the greater or lesser values of a character string based upon the ASCII code equivalent of each character.