length()
Returns the number of characters in a string passed as parameter.
Syntax
length(
   str STRING )
  RETURNS INTEGER
- str is any valid character string expression supported by the language.
 
Usage
The length() function counts the length of a character string.
Note: 
Unlike the STRING.getLength() method, the LENGTH() function does not
count the trailing blanks.
If the parameter is NULL,
 the function returns zero.
Important: 
When using byte length semantics, the length is expressed in bytes. When using char length semantics, the unit is characters. This matters when using a multibyte locale such as UTF-8.