- Consider the following database.
EMPLOYEE(Name, SSN, Salary, DNO, SupervisorSSN, JobCode)
DEPARTMENT(DNO, TotalSalary, ManagerSSN)
STARTING_PAY(JobCode, StartPay)
Note that Dept_No in EMPLOYEE table is foreign key.
Based on Active Database Concepts, answer the following questions:
Write the active rules (triggers) for following two events
- Limit all salary increases to 50%.
- All new hires for a given job code get the same starting salary, which is available in the STARTING_PAY table.
2) Explain Hybrid fragmentation
- For each of the following relation schemas and sets of FD’s:
- a) R(A, B, C, D) with FD’s A B -> C, C -> D, and D-> A.
- b) R (A ,B ,C ,D ) with FD’s B -> C and B-> D
Do the following:
- i) Indicate all the BCNF violations. Do not forget to consider FD’s that are not in the given set, but follow from them. However, it is not necessary to give violations that have more than one attribute on the right side.
- ii) Decompose the relations, as necessary, into collections of relations that are in BCNF.