Beginning SQL

LastName LOWER(SUBSTRING(LastName,1,1)) + SUBSTRING(LastName,2,LEN(LastName) - 1)
Doors doors
Dales dales
Botts botts
The SOUNDEX() and DIFFERENCE() Functions
So far, all searching and matching with strings have been based on their actual characters. The following
SQL, for example, matches only the FirstName Jack:
SELECT FirstName
WHERE FirstName = ‘Jack’;
Sometimes, however, the exact spelling of a name might not be known; you might have only an idea of
what it sounds like. It’s exactly this problem that the SOUNDEX() and DIFFERENCE() functions are
designed to conquer. Unfortunately MS Access doesn’t support SOUNDEX() or DIFFERENCE(). MySQL,
on the other hand, supports SOUNDEX() but doesn’t support DIFFERENCE().
The SOUNDEX() function converts a string into a special four-character code representing the way the
string sounds rather than how it is spelled. Its basic syntax is as follows:
SOUNDEX(name_to_be_converted_to_code);
Note that MS Access doesn’t support the SOUNDEX() function.
The first character in the code is always the first character of the original string. Following that is a threedigit
number representing how the word sounds based on the SOUNDEX() guidelines. SOUNDEX() was
actually first developed long before database systems, for use with the U.S. census and patented in 1918.
For example, the following SQL returns the SOUNDEX() values for first names in the MemberDetails table:
SELECT FirstName,SOUNDEX(FirstName)
FROM MemberDetails;
The query results are as follows:
FirstName SOUNDEX(FirstName)
Katie K300
Susie S200
Doris D620
Jenny J500
John J500
Jack J200
Manipulating Data
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