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Oracle SQL and PL/SQL Handbook: A Guide for Data Administrators, Developers, and Business Analysts by John Adolph Palinski

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Creating an Entity Relationship Diagram

This section portrays a real example of the creation of an entity relationship diagram (ERD). I don’t intend that this discussion be all-inclusive of this topic; however, I would like you to see the basic steps that are taken in the event that you need to create one:

1.
Identify the entities.
2.
Define the identifiers.
3.
Define the relationships.
4.
Determine cardinality and ordinality of the relationship.
5.
Determine descriptive attributes. Move these to related entities.
6.
Create the ERD.
7.
Review and refine the ERD.

Identifying the Major Entities

The attributes of the database are contained in the f lows of the system’s data f low diagram (DFD). The analyst reviews this set of data, identifies ...

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