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A Brief History of the Relational Model

Several types of database models exist. Some, such as hierarchical and network, are used only on legacy systems, while others, such as relational, have gained wide acceptance. You might also encounter discussions in other books about object, object-relational, or online analytical processing (OLAP) models. In fact, extensions have been defined in the SQL Standard to support these models, and some commercial database systems have implemented some of the extensions. For our purposes, however, we will focus strictly on the relational model and the core of the international SQL Standard.

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Cover of SQL Queries for Mere Mortals: A Hands-On Guide to Data Manipulation in SQL, Second Edition

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