University:
California State University, Northridge
Course:
COMP 440 | Database Design
Academic year:

2024
Views:

481

Pages:

5
Author:

Samuel K.

Nyi Nyi Moe Htet COMP 440 ERD & Relational Diagrams 10. EMPLOYEE TABLE PK is EMP_CODE. FK is JOB_CODE. JOB TABLE PK is JOB_CODE. FK is None. BENEFIT TABLE PK is a composite key which consists of two foreign keys: EMP_CODE and PLAN_CODE. FKs are EMP_CODE and PLAN_CODE. PLAN TABLE PK is PLAN_CODE. FK is None. 13. and 14. EMPLOYEE TABLE Entity Integrity: Yes, because the table has a primary key (EMP_CODE) which uniquely identifies each record and does not contain any null values. Referential Integrity: Yes, because JOB_CODE column is a foreign key referencing the JOB table and all JOB_CODE values in the EMPLOYEE table exist in the JOB table. BENEFIT TABLE Entity Integrity: Yes, because the table has a composite primary key (EMP_CODE, PLAN_CODE), which uniquely identifies each record and does not contain null values. Referential Integrity: Yes, because EMP_CODE is a foreign key referencing the EMPLOYEE table and all EMP_CODE values in the BENEFIT table exist in the EMPLOYEE table. PLAN_CODE is a foreign key referencing the PLAN table and all PLAN_CODE values in the BENEFIT table exist in the PLAN table. JOB TABLE Entity Integrity: Yes, because the table has a primary key (JOB_CODE) which uniquely identifies each record and does not contain any null values. Referential Integrity: N/A PLAN TABLE Entity Integrity: Yes, because the table has a primary key (PLAN_CODE) which uniquely identifies each record and does not contain any null values. Referential Integrity: N/A 15. ERD 16. Relational Diagram