Use the keyref statement of XML Schema to de?ne the following referential integrity for the document in Figure 15.4:

a. Every course code in a CourseTaken element must refer to a valid course.
b. Every course code in a Class element must refer to a valid course.


a.









where adm is the namespace pre?x used for the schema of the document in Figure 15.4 and CourseKey is de?ned as the primary key for Course elements:









b.


refer="adm:CourseKey">





where CourseKey was de?ned above.

Computer Science & Information Technology

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Answer the following statement true (T) or false (F)

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Computer Science & Information Technology