These books address databases, both their use and programming. I'm a heavy user of MySQL under Linux, and I'm learning about PalmOS databases as well.
The Practical Sql Handbook : Using Structured Query Language
Buy it!
by Judith S. Bowman, Sandra L. Emerson (Contributor), Marcy Darnovsky (Contributor)
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Palm Database Programming: The Complete Developer's Guide
Buy it!
by Eric Giguere
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Programming the Perl DBI
Buy it!
by Alligator Descartes, Tim Bunce
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