'''An Introduction to Database Systems'''
C.J. Date
ISBN: ISBN:0201385902

A textbook explaining the relational model in great detail, and
written by a well-known relational database commentator.
New editions of this book are regularly released every two or three years, so the ISBN
might be out of date; the ISBN is for the seventh edition, but you should check
if there's a newer one.
(On the other hand, old editions are still perfectly
readable and useful, and likely can be found much more cheaply.)

'''Database Management Systems'''
Raghu Ramakrishnan and Johannes Gehrke
ISBN: ISBN:0072465638
McGraw-Hill

A textbook on database concepts (relational algebra, entity-relationship modelling), programming (SQL), implementation (files, indices, hashes, query optimization, transactions), and "advanced concepts" (distributed databases, data mining, object-databases).  This book is an alternative to Date's book.

'''Managing Gigabytes: Compressing and Indexing Documents and Images'''
Ian H. Witten, Alistair Moffat, Timothy C. Bell

ISBN:1558605703,
Morgan Kaufmann, May 1999.

Discusses algorithms and techniques for compressing, indexing, and
searching large document archives.  It's aimed at applications where
you write your own disk storage and compression routines, and doesn't
use SQL.

'''The Data Access Handbook: Achieving Optimal Database Application Performance and Scalability'''
John Goodson and Robert A. Steward

ISBN: 0137143931
Prentice Hall, March 2009.

Addresses the issues of connecting languages to databases in a generic sense.

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