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Representation of Tables

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The Entity Relationship Diagrammer shows the tables and their relationships to each other in strict conformance with the IDEF1X standard.

We can distinguish between two types of tables:

Tables that do not have any foreign-key relationships with another table are called Independent tables. In the diagram, they are represented as straight-cornered rectangles.

Tables containing a foreign key referencing another table are called Dependent tables. They are represented as rectangles with rounded corners.

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The name of the table is placed above the rectangle, and column information is located inside it. A horizontal line divides this area into two parts:

Primary key columns

All other columns.

Each line contains the following information about a single column:

An icon that represents the data type of the column. It can be disabled through the auto-layout dialog.

the column name

the letters (FK) representing foreign key columns.

Also, through the auto-layout option, the display of columns can be limited to just those columns that form part of a key.