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This page is for anyone using an ERD to define a data structure. It explains the properties for relationships.
Overview
Relationships are part of ERDs; see Understanding ERDs and Adding Content to an ERD. They represent the connection between a primary key attribute in one stream and an attribute in another stream. For example, the relationship line in the screenshot below shows that Teacher.Department contains the same data as the primary key SchoolDept.UID.
A stream's unique identifier is its primary key, and where it occurs in another stream, it is a foreign key.
The screenshot above shows that a relationship line has a one termination at the primary key and an arrow pointing to the foreign key. This line represents the 1 and many ends of the relationship.
PhixFlow automatically sets the properties for a relationship, except the description. To add a relationship description, click on the relationship line to open its properties. Relationships are not listed in the repository.