Page 301 - Data Architecture
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Chapter 8.1: A Brief History of Data Architecture




































               Fig. 8.1.10 Different relationships.


           The DBMS were useful for organizing data both for batch processing and for online
           transaction processing. Many systems were built running transactions under the DBMS.


           Soon, there came another notion about the way data should be logically organized. That
           method was through what was termed a relational database management system.


           In the relational database management system, data were “normalized.” Normalization
           meant that there was a primary key for each table and the attributes in the table
           depended on the key of the table for their existence. The tables were able to be related to
           each other by means for a key/foreign key relationship. Upon access of the tables, the
           tables could be “joined” by means of pairing up the appropriate key and foreign key.


           Fig. 8.1.11 shows a relational table.















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