''From SqlMyopia, on the topic of relational calculus & algebra:''

My favorite book to cover all of these topics is FundamentalsOfDatabaseSystems by Elmasri and Navathe. It covers the math, as well as SQL. -- KyleBrown

''FundamentalsOfDatabaseSystems'' by RamezElmasri and ShamkantNavathe, Addison-Wesley, 1999 (3rd ed.), ISBN0805317554
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Why are database reference books often close to 1000 pages?  The topic has a well-formed theoretical basis (compared to Operating Systems, say) and very well-understood role.  It should be possible to distill this into something more like KernighanAndRitchie or Iverson's book on AplLanguage or Allen's Probability, Statistics, and Queueing theory (talk about covering a lot in a short, readable book).  If I were to deconstruct most DB tomes I would conclude

(A) authors have an inferiority complex about their field
(B) authors condescend to their readers (O'Reilly T-SQL book is an example)

-- PeteProkopowicz
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CategoryBook