Consider the following three relations Employee (E) sex 101 102 103 104 105 Work
ID: 3753280 • Letter: C
Question
Consider the following three relations Employee (E) sex 101 102 103 104 105 Work On (W) 150,000 150,000 100,000 100,000 80,000 James ar Patricia Robert 101 101 102 102 102 103 104 year 2015 2016 2015 2016 2017 2017 2018 2 Project (P) mgr eid 102 103 104 budget 30,000,000 20,000,000 10,000,000 DataBase DataMini The key attributes are underlined. Work On.eid refers to Employee.eid, Work On.pid refers to Project pid, and Project.mgr_eid refers to Employee.eid. Let E be Employee, let W be Work On, and let P be Project. Show the Result of the following Relatonal Algebra (RA) expression 1 ) ename, pname (E ba w ba ( budget» 20,000,000 P) ) 2 ) ename, pname ( ( salaryExplanation / Answer
1. ename, pname (E W ( budget > 20000000 P))
2. ename, pname (( salary < 80000 E) W P)
3. ename (E W pname = 'DataBase' and pname = 'DataMining' P)
5. ename (E W pname = 'DataBase' or pname = 'Data warehouse' P)
6. (EWP (1 e_eid, 2 e_ename, 3 w_eid, 4 w_pid, 5 p_pid, 6 p_pname), ( eid, ename E) eid, pid W pid, pname pname='DataMining'P)
e_eide_enamew_eidw_pidp_pidp_pname101James10112DataMining101James10122DataMining101James10212DataMining101James10222DataMining101James10232DataMining101James10322DataMining101James10432DataMining102Mary10112DataMining102Mary10122DataMining102Mary10212DataMining102Mary10222DataMining102Mary10232DataMining102Mary10322DataMining102Mary10432DataMining103John10112DataMining103John10122DataMining103John10212DataMining103John10222DataMining103John10232DataMining103John10322DataMining103John10432DataMining104Patricia10112DataMining104Patricia10122DataMining104Patricia10212DataMining104Patricia10222DataMining104Patricia10232DataMining104Patricia10322DataMining104Patricia10432DataMining105Robert10112DataMining105Robert10122DataMining105Robert10212DataMining105Robert10222DataMining105Robert10232DataMining105Robert10322DataMining105Robert10432DataMining
7.
E.ename P.pname James DataBase Mary DataBase