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DTM Data Modeler uses basic elements of IDEF1X notation. IDEF1X is a method for designing relational databases.
There are two basic elements of model: entity and relationship. In IDEF1X notation, entities are either
independent (also known as parent or master) or dependent (also known as child or detail). Also, relationships
are either identifying or non-identifying.
Any entity must contain one or more attributes. Attributes are properties used to describe an entity.
Any attribute must have name and type (data type like integer or char).
A key is a set of attributes that uniquely identify an entity instance. DTM Data Modeler supports primary keys
only and every entity has only one primary key. The attributes of primary key displayed above the horizontal line in the entity box.
The following table describes method elements that can be used with DTM Data Modeler:
| Model element |
Visual representation |
| Independent Entity |
 |
| Dependent Entity |
 |
Identifying relationship
|
 |
Non-identifying relationship
|
 |
| Primary Key |
 |
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