Specify queries (a), (b), (c), (e), (f), (i), and (j) of Exercise 6.16 in both tuple and domain relational calculus.

What will be an ideal response?


(a) Retrieve the names of employees in department 5 who work more than 10 hours per
week on the 'ProductX' project.
Tuple relational Calculus:
{ e.LNAME, e.FNAME | EMPLOYEE(e) AND e.DNO=5 AND (EXISTS p) (EXISTS w)
(
WORKS_ON(w) AND PROJECT(p) AND e.SSN=w.ESSN AND
w.PNO=p.PNUMBER AND
p.PNAME='ProductX' AND w.HOURS>10 ) }
Domain relational Calculus:
{ qs | EMPLOYEE(qrstuvwxyz) AND z=5 AND (EXISTS a) (EXISTS b) (EXISTS e)
(EXISTS f)
(EXISTS g) ( WORKS_ON(efg) AND PROJECT(abcd) AND t=e AND f=b AND
a='ProductX' AND
g>10 ) }

(b) List the names of employees who have a dependent with the same first name as
themselves.
Tuple relational Calculus:
{ e.LNAME, e.FNAME | EMPLOYEE(e) AND (EXISTS d) ( DEPENDENT(d) AND
e.SSN=d.ESSN
AND e.FNAME=d.DEPENDENT_NAME ) }
Domain relational Calculus:
{ qs | (EXISTS t) (EXISTS a) (EXISTS b) ( EMPLOYEE(qrstuvwxyz) AND
DEPENDENT(abcde)
AND a=t AND b=q ) }

(c) Find the names of employees that are directly supervised by 'Franklin Wong'.
Tuple relational Calculus:
{ e.LNAME, e.FNAME | EMPLOYEE(e) AND (EXISTS s) ( EMPLOYEE(s) AND
s.FNAME='Franklin' AND s.LNAME='Wong' AND e.SUPERSSN=s.SSN ) }
Domain relational Calculus:
{ qs | (EXISTS y) (EXISTS a) (EXISTS c) (EXISTS d) ( EMPLOYEE(qrstuvwxyz) AND
EMPLOYEE(abcdefghij) AND a='Franklin' AND c='Wong' AND y=d ) }

(e) Retrieve the names of employees who work on every project.
Tuple relational Calculus:
{ e.LNAME, e.FNAME | EMPLOYEE(e) AND (FORALL p) ( NOT(PROJECT(p)) OR
(EXISTS w) (
WORKS_ON(w) AND p.PNUMBER=w.PNO AND w.ESSN=e.SSN ) ) }
Domain relational Calculus:
{ qs | (EXISTS t) ( EMPLOYEE(qrstuvwxyz) AND (FORALL b) (
NOT(PROJECT(abcd)) OR
(EXISTS e) (EXISTS f) (WORKS_ON(efg) AND e=t AND f=b) ) }

(f) Retrieve the names of employees who do not work on any project.
Tuple relational Calculus:
{ e.LNAME, e.FNAME | EMPLOYEE(e) AND NOT(EXISTS w) ( WORKS_ON(w)
AND
w.ESSN=e.SSN ) }
Domain relational Calculus:
{ qs | (EXISTS t) ( EMPLOYEE(qrstuvwxyz) AND NOT(EXISTS a) (
WORKS_ON(abc) AND a=t )
) }

(i) Find the names and addresses of employees who work on at least one project located
in Houston but whose department has no location in Houston.
Tuple relational Calculus:
{ e.LNAME, e.FNAME, e.ADDRESS | EMPLOYEE(e) AND (EXISTS p) (EXISTS w) (
WORKS_ON(w) AND PROJECT(p) AND e.SSN=w.ESSN AND
w.PNO=p.PNUMBER AND
p.PLOCATION='Houston' AND NOT(EXISTS l) ( DEPT_LOCATIONS(l) AND
e.DNO=l.DNUMBER
AND l.DLOCATION='Houston' ) ) }
Domain relational Calculus:
{ qsv | (EXISTS t) (EXISTS z) ( EMPLOYEE(qrstuvwxyz) AND (EXISTS b) (EXISTS c)
(EXISTS e)
(EXISTS f) ( WORKS_ON(efg) AND PROJECT(abcd) AND t=e AND f=b AND
c='Houston' AND
NOT(EXISTS h) NOT(EXISTS i) ( DEPT_LOCATIONS(hi) AND z=h AND i='Houston'
) ) }

(j) List the last names of department managers who have no dependents.
Tuple relational Calculus:
{ e.LNAME | EMPLOYEE(e) AND (EXISTS d) ( DEPARTMENT(d) AND
e.SSN=d.MGRSSN AND
NOT(EXISTS x) (DEPENDENT(x) AND e.SSN=x.ESSN) ) }
Domain relational Calculus:
{ s | (EXISTS t) ( EMPLOYEE(qrstuvwxyz) AND (EXISTS c) ( DEPARTMENT(abcd)
AND t=c
AND NOT(EXISTS e) (DEPENDENT(efghi) AND e=t) ) }

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