>>-SOUNDEX--(--expression--)-----------------------------------><
The schema is SYSFUN.
Returns a 4 character code representing the sound of the words in the argument. The result can be used to compare with the sound of other strings.
The argument can be a character string that is either a CHAR or VARCHAR not exceeding 4 000 bytes.
The result of the function is CHAR(4). The result can be null; if the argument is null, the result is the null value.
The SOUNDEX function is useful for finding strings for which the sound is known but the precise spelling is not. It makes assumptions about the way that letters and combinations of letters sound that can help to search out words with similar sounds. The comparison can be done directly or by passing the strings as arguments to the DIFFERENCE function (see DIFFERENCE).
Example:
Using the EMPLOYEE table, find the EMPNO and LASTNAME of the employee with a surname that sounds like 'Loucesy'.
SELECT EMPNO, LASTNAME FROM EMPLOYEE
WHERE SOUNDEX(LASTNAME) = SOUNDEX('Loucesy')
This example returns the following:
EMPNO LASTNAME ------ --------------- 000110 LUCCHESSI