Chapter 9 Working with Data Models
The following CDM/LDM model checks are made on entities:
| Check | Description and Correction |
|---|---|
| Entity name and code uniqueness | Entity names and codes must be unique in the namespace.
Manual correction: Modify the duplicate name/code Automatic correction: Appends a number to the duplicate name/code. |
| Entity name and code maximum length | The entity name and code length is limited to a maximum length of 254 characters specified in the naming conventions of the model options.
Manual correction: Modify the entity name/code length to meet this requirement. Automatic correction: Truncates the entity name/code length to the maximum length specified in the naming conventions. |
| Existence of attributes | An entity must always contain at least one attribute.
Manual correction: Add an attribute to the entity or delete the entity. Automatic correction: None. |
| Number of serial types > 1 | An entity cannot have more than one serial type attribute. Serial types are automatically calculated values.
Manual correction: Change the types of the appropriate entity attributes to have only one serial type attribute. Automatic correction: None. |
| Existence of identifiers | An entity must contain at least one identifier.
Manual correction: Add an identifier to the entity or delete the entity. Automatic correction: None. |
| Existence of relationship or association link | An entity must have at least one relationship or association link.
Manual correction: Add a relationship or an association link to the entity or delete the entity. Automatic correction: None. |
| Redundant inheritance | An entity inherits from another entity more than once. This is redundant and adds nothing to the model.
Manual correction: Delete redundant inheritances Automatic correction: None. |
| Multiple inheritance | An entity has multiple inheritance. This is unusual but can be tolerated if you defined this check as a warning.
Manual correction: Make sure that the multiple inheritance is necessary in your model. Automatic correction: None. |
| Parent of several inheritances | An entity is the parent of multiple inheritances. This is unusual but can be tolerated if you defined this check as a warning.
Manual correction: Verify if the multiple inheritances could not be merged. Automatic correction: None. |
| Redefined primary identifier | Primary identifiers in child entities must be the same as those in their parents.
Manual correction: Delete those primary identifiers in the child entities that are not in the parent entity. Automatic correction: None. |
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