C.J. Date 
Relational Database Dictionary [PDF ebook] 
A Comprehensive Glossary of Relational Terms and Concepts, with Illustrative Examples

Avoid misunderstandings that can affect the design, programming, and use of database systems. Whether you’re using Oracle, DB2, SQL Server, My SQL, or Postgre SQL, The Relational Database Dictionary will prevent confusion about the precise meaning of database-related terms (e.g., attribute, 3NF, one-to-many correspondence, predicate, repeating group, join dependency), helping to ensure the success of your database projects. Carefully reviewed for clarity, accuracy, and completeness, this authoritative and comprehensive quick-reference contains more than 600 terms, many with examples, covering issues and concepts arising from the relational model of data.This one-of-a-kind dictionary provides a single, compact source where DBAs, database designers, DBMS implementers, application developers, and database professors and students can find the accurate definitions they need on a daily basis, information that isn’t readily available anywhere else. If you’re working with or learning about relational databases, you need this pocket-sized quick-reference.