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| Question | Answer |
| What is an attribute? | An attribute describes a property of an entity or a relationship. For example, "student" might have the attributes "id, age, major". |
| Explain what is being conveyed here. What are the constraints? | Each employee works in at most one department. |
| Explain what is being conveyed here. What are the constraints? | Each employee can manage at most one department. Each department is managed by at most one employee. |
| True or false: A weak entity cannot be uniquely identified without the candidate key of its owner entity. | False. A weak entity cannot be uniquely identified without the PRIMARY key of its owner entity. |
| The relationship between an owner entity and a weak entity is ___ to ___. | one to many (one owner, many weak entities) |
| True or false: By default, ISA hierarchies do not enforce covering constraints. | True |
| True or false: By default, overlap between inheriting entities in an ISA hierarchy is allowed. | False. Such overlap is disallowed by default. |
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