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.
Chapter 8.1: A Brief History of Data Architecture