Primary Key

A Primary Key uniquely identifies a record in a Table and can consist of one or more columns. A Primary Key that involves several columns is a complex Primary Key; for example, a column LastName might not be unique within a Table, so a Primary Key is created from the LastName, FirstName and DateOfBirth columns. In Enterprise Architect, on a diagram:

·The column is defined by an attribute and its involvement in the Primary Key is indicated by the flag PK on the attribute
·The Primary Key itself is identified by a stereotyped operation that defines the constraints and behaviour associated with the implementation of the Primary Key


The SQL Server Primary Key Fill Factor is defined within the Primary Key operation, as the Tagged Value FILLFACTOR with a numerical value.

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Learning Center topics

·(Alt+F1) | Enterprise Architect | Database Engineering | Physical Data Model | Add Primary Key