Programming the Perl DBI is excellent. Buy it. Read it.
The only O'Reilly book I've felt I wasted my money on is 'MySQL & mSQL'. That book is nothing more than a rehash of 'perldoc DBI'. For a good mySQL book (if that's what you're using, of course), get the MySQL by Paul DuBois from New Riders.
The remaining 10 or so O'Reilly books I have I've felt are good values.
--Chris
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