Details: Specifying referential constraint update rules

 

You can specify one of these values for the UPDRULE parameter. The UPDRULE parameter identifies the update rule for the constraint relationship between parent and dependent files. The update rule specifies the action that the system takes when you update the parent file.

• *NOACTION (the default value)

  • Record update in a parent file does not occur if there is a matching foreign key value in the dependent file.

• *RESTRICT

  • Record update in a parent file does not occur if a value of the non-null parent key matches a foreign key value.

  The system enforces an update *RESTRICT rule immediately when you attempt the update operation. The system enforces other constraints at the logical end of the operation. For example, a trigger program can add a parent record if one does not exist. The *RESTRICT rule does not prevent the violation.

 

Parent topic:

Specifying referential constraint rules