When a 1-1 relationship is converted into two foreign keys,if the relationship is optional for one of the entity types,the corresponding foreign key may be eliminated.

Question

Quizplus · Accepted Answer

If the relationship is optional for one of the entity types, then there may not be a corresponding record in the related table, so the foreign key for that entity type would be null. In this case, it can be eliminated.

When a 1-1 Relationship Is Converted into Two Foreign Keys,if