CS-06 Data Base Management System June-2002
Question Paper of CS-06 Data Base Management System June-2002
Q.l(a). Draw E-R diagram for a departmental store, after determining the entities of interest and the relationship that exist between these entities. Also construct a tabular representation of the entities and relationships. Are there any attributes (or collections of attributes) in each entity set that would uniquely identify an instance of the entity set?
(b) What problems are caused by data redundancies? Can data redundancies be completely eliminated when the database approach is used? Explain.
© Explain why first normal form is acceptable for data processing applications.
(d)Consider the relational database:
EMPLOYEE (ENO, EName, Skill, Pay-Rate, Date)
POSITION (Posting_No, Skill)
DUTY_ALLOCATION (PostingJVo, ENO, Shift)
Give expressions in SQL for the following:
(i) Find the names of employees who are assigned to all positions that require a clerk’s skill.
(ii) Get employees who are working either on the date 19860419 or 19860420.
(iii) Find the names and rate of pay of all employees who are not allocated a duty.