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Relationships Between Tables
Tables in PhixFlow are relational, which means that information in one table can be related to information in another table. Data can then be accessed in many different views without requiring duplication. See Creating Dashboards and Reports (Charts and Graphs).
A line connects the Primary Key or Secondary Key of one table to a Foreign Key in a different table and represents a relationship. See Relationship. Click on the image below to enlarge it.
One-to-Many and Many-to-One Relationships
The relationship line between a Primary Key or Secondary Key and Foreign Key represents a one-to-many relationship. In the below example, one teacher runs many courses.
A many-to-one relationship is implied when you read a relationship in the opposite direction. In the below example, many courses are run by one by one teacher. Click on the image below to enlarge it.
Many-to-
ManyMany Relationships
Many-to-many relationship can be supported with an intermediate table.
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A many-to-many relationship is created when there is an intermediate table with a Foreign Key from each of the related tables. In the example used above, many students take many courses, and so a many-to-many relationship is created using the intermediate table, CourseAttendee. |
Multi-Hop Relationships
Multi-hop relationships are relationships between tables without a direct relationship. PhixFlow supports multi-hop relationships to a distance of 4 hops. In the example ERD below, the relationship distance between the Buildings and Bookings table is 2 hops, and between the Buildings and Departments table is 4 hops.
