Reduce the ER diagram to relation table solved exercise

How to reduce an ER diagram to tables? Reduction of ERD to relation schema, Convert Entity Relationship diagram to set of tables, ERD to relation schema examples, mapping ER diagram to relational tables

Reduce (convert) the following ER diagram to relational schema

ER components	Given component	Result
Strong Entity Set Rule: Strong entity set can be directly converted into table.	(a) STUDENT (b) SUBJECT (c) CLASS	(a) STUDENT (Student_ID, Student_Name, DOB, Address)  (b) SUBJECT (Subject_ID, Subject_Name, Teacher) (C) CLASS (Class_ID, Class_Name)
Derived attribute Rule: No need to create a column in the table for derived attribute.	Age in STUDENT table	No changes
Composite attribute Rule: Replace the composite attribute with its component attributes.	Address in STUDENT table	STUDENT (Student_ID, Student_Name, DOB, Door, Street, City, Pin)
1-1, 1-n, and n-1 Relationships Rule: Include the primary key of one side entity set as the foreign key of other side entity set.	Attends (1-1 from STUDENT to CLASS) Studies (1-n from STUDENT to SUBJECT)	CLASS (Class_ID, Class_Name, Student_ID) SUBJECT (Subject_ID, Subject_Name, Teacher, Student_ID)
Descriptive attribute Rule: An attribute that is part of a relationship is descriptive. Include the descriptive attributes to 1 side as shown above.	DateOfJoin, Hours# of Attends relationship.	CLASS (Class_ID, Class_Name, Student_ID, DateOfJoin, Hours#)
Weak entity set Rule: Weak entity set is totally participated (existence dependent) on the strong entity set. Include the primary key of strong entity set into the weak entity set as foreign key.	(d) SECTION	SECTION (Section_ID, Section_Name, Class_ID)
Weak relationship Rule: No need to create as a table. If created, then the table is redundant.	Has	No changes

Final set of relation schemas: (Primary keys are underlined)

STUDENT (Student_ID, Student_Name, DOB, Door, Street, City, Pin)

CLASS (Class_ID, Class_Name, Student_ID, DateOfJoin, Hours#)

Student_ID is the foreign key refers STUDENT table

SUBJECT (Subject_ID, Subject_Name, Teacher, Student_ID)

Student_ID is the foreign key refers STUDENT table

SECTION (Section_ID, Class_ID, Section_Name)

Class_ID is the foreign key refers CLASS table

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