Referential integrity is enforced using:

Question

BlackTom AI · Accepted Answer

Begin by identifying the core concept: referential integrity in relational databases ensures that a value in a foreign key column corresponds to an existing value in the referenced primary key column or is NULL.
Option 1: Composite keys. While composite keys are a type of key formed by multiple attributes, they are not specifically what enforces referential integrity across tables. They may be used as primary keys, but they themselves do not guarantee references to other tables.
Option 2: Primary keys. Primary keys uniquely identify records within a table, and while they are referenced by foreign keys, the primary key alone does not enforce referential integrity. It is the foreign key constraint that enforces that values in a child table must match those in the parent table’s primary key (or be NULL, depending on the design).
Option 3: Superkeys. A superkey is any set of one or more attributes that can uniquely identify a row in a table, but this concept does not by itself enforce cross-table referential constraints. Referential integrity relies on foreign keys linking tables, not on the abstract notion of a superkey.
Option 4: Foreign keys. This is the mechanism that enforces referential integrity: a foreign key in one table references a primary key (or unique key) in another table, ensuring that references are valid and consistent across the relationship.
In summary, the only option that directly enforces the referential integrity constraint between two tables is the use of foreign keys.

Referential integrity is enforced using:

查看解析

登录即可查看完整答案

类似问题

If a 1:M relationship is mandatory on both sides, which of the following is true?

Why is a foreign key important in relational databases?

Which of the following is a characteristic of a foreign key?

A foreign key in one table must refer to:

Which of the following is NOT true about a foreign key that connects two tables in a database?

Which of the following is not a feature of a Foreign Key?

The FOREIGN KEY constraint should be added to which table?

更多留学生实用工具

考试浏览器助手

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