Architecting and designing > Data modeling > The Physical Data Model > Objects in a PDM > Indexes
  
Indexes
Indexes specify columns that can be used to locate individual records within a database table. A unique index represents a candidate key, that is, the columns that comprise the index can uniquely identify an individual record. The primary key index is a unique index comprised of the columns in the Primary Key Constraint.
An index is the physical equivalent of an access path in the entity relation model.
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Index definition
Indexes specify the columns that can be used to locate an individual record that is included in the database table.
The Index Editor is used to define indexes within a table. This editor is embedded in the Table Editor and can only be opened by selecting the Index tab from a table definition dialogue. It always includes a Modeling Properties page and can include additional pages depending on the target DBMS.
Index properties vary by target DBMS.
Source and key properties for indexes
System Architect maintains key properties that qualify the index name, and source properties when the Physical Data Model is created from another SA diagram. The key and source properties are not visible in the index editor, but be output on reports.
Database name
See Database name.
Source Access Path
Filled in by System Architect when a Physical Data Model diagram is generated from an Entity Relation diagram. This property is not displayed in the Index definition dialog, but is available to the System Architect reporting system.
Source diagram name
See Source Diagram Name.
Table Name
The qualified name of any index includes the name of the table in which it belongs to.
See also
Objects in a PDM