In a 1:1 relationship, the primary key placement is arbitrary.

More Questions from Data Models into Database Designs

• For every relationship, there are six possible sets of minimum cardinalities.
• Cascading updates refers to child rows being automatically deleted when a parent row is deleted.
• Surrogate keys have much meaning for users.
• When the parent entity is required, a new child row can always be inserted.
• When transforming an entity-relationship model into a relational database design, each entity is represented as a table.
• When the parent entity is required and the parent has a surrogate key, update actions can be ignored.
• An ideal primary key is short, numeric and seldom changing.
• Intersection tables are ID-dependent on both their parent tables.
• The terms alternate key and candidate key mean the same thing.
• When the child entity is required, we are restricted from creating a new parent row without also creating a corresponding child row at the same time.

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