Inspect the following conceptual model

Identify the primary key of the Store entity

Question

Inspect the following conceptual model

Identify the primary key of the Store entity

BlackTom AI · Accepted Answer

StoreID uniquely identifies each Store, so it is the primary key.

1) Relevant knowledge points and concepts
- Primary key: an attribute (or minimal set of attributes) that uniquely identifies each instance of an entity.
- Foreign key: an attribute that links to the primary key of another entity (used for relationships).
- Composite key: more than one attribute used together to uniquely identify an instance; only used when no single attribute is sufficient.
- Uniqueness vs. descriptive attributes: attributes like Name are usually descriptive and may not be unique.

2) Step-by-step reasoning process
- Inspect the Store entity: attributes shown are StoreID and Name.
- Determine whether any single attribute can uniquely identify a Store: StoreID is a typical identifier (ID) intended to be unique.
- Consider whether RegionID must be part of the primary key: the diagram shows Region contains Store (one-to-many). That implies a Store belongs to one Region, so RegionID will appear as a foreign key in Store, but not necessarily as part of the primary key.
- Evaluate if a composite key is needed: only necessary if StoreID is not globally unique and is only unique within a Region. The model explicitly lists StoreID as an attribute; typical modeling practice is to use a single StoreID as the primary key.
- Assess Name: store names are not guaranteed unique and are descriptive, so they should not be part of the primary key.

3) Intermediate "calculation" steps (logical)
- Is StoreID present? Yes.
- Does StoreID uniquely identify a store? Yes (conventional ID attribute).
- Is there evidence StoreID is only unique within Region? No evidence; relationship indicates Region→Store (one-to-many), meaning RegionID is a foreign key, not required for uniqueness.

4) Why the correct answer is correct
StoreID is the minimal attribute that uniquely identifies each Store instance. It meets the definition of a primary key without needing RegionID or Name.

5) Why the other options are incorrect
- RegionID, StoreID: makes a composite key unnecessary and redundant if StoreID is already unique.
- RegionID, StoreID, Name: adds an extra descriptive attribute (Name) that is not needed and violates minimality.
- StoreID, Name: includes Name which is descriptive and not required for uniqueness.

6) Conclusion
Therefore the primary key of Store is StoreID, matching the provided correct answer.

Inspect the following conceptual model Identify the primary key of the Store entity单项选择题

类似问题

The table is the basic building block in database design. An attribute (or column) that uniquely identifies a particular object (or row) in the table is called:

If order_id is declared as a PRIMARY KEY, which of the following are guaranteed? Choose all that apply.

什么是主键？

Each table in a relational database has one field designated as its primary:

Which of the following best describes the purpose of a primary key?

After transforming the above ERD to a Relational Schema, what is the primary Key for patient treatment?

In a relational database, which of the following about Primary Key is FALSE

A primary unique key:

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单