PPSC Lecturer Computer Science Syllabus Quiz 6 A.J. Bhatti September 3, 2020 Welcome to your PPSC Lecturer Computer Science Syllabus Quiz 6 Name Email 1. Which normal form is considered adequate for relational database design? 2NF 3NF 4NF BCNF 2:Which of the following option is correct? Consider the relational table with a single record for each registered student with the following attributes: Registration_Num: unique registration of each registered student UID: Unique Identity Num,Uniques for each citizen(national level) BankAccount_Num:unique account number ate the bank.a student can have multiple accounts or joint accounts.this attribute stores the primary account number Name: name of the student Hostel_room: room number of the hostel a. BankAccount_num is a candidate key. b. Registration_num can be a primary key c. UID is a candidate key if all students are from same country d. If S is a super key such that S ∩ UID is NULL then S ꓴ UID is also a super key 3:Which of the following is used to denote the selection operation in relational algebra? Pi (Greek) Sigma (Greek) Lambda (Greek) Omega (Greek) 4:For select operation the ________ appear in the subscript and the ___________ argument appears in the paranthesis after the sigma. Predicates, relation Relation, Predicates Operation, Predicates Relation, Operation 5. Which is a join condition contains an equality operator: a) Equijoins b) Cartesian c) Natural d) Left 6:If matching tuples are not found, the kind of OUTER JOIN operation which keeps all the tuples of first and second relation is classified as LEFT OUTER JOIN FULL OUTER JOIN HALF OUTER JOIN DOWNWARD JOIN 7.which of the following is true ? Every relation in 3NF is also in BCNF A relation R is in 3NF if every non-prime attribute of R is fully functionally dependent on every key of R Every relation in BCNF is also in 3NF No relation can be in the both 3NF and BCNF 8........for a database relation R(a,b,c,d) where domain of a,b,c and d include only automatic includes only atomic values , only the following functional dependencies and those that can be inferred from them hold a→ c b→ d The relation is in First normal form but not in second normal form Second normal form but not in third normal Third normal form None of the above 9. in “many to many relationship” one instance of first entity can be mapped with many instances of second entity Select correct option: a. true b. false 10. Compute R ⋈ S. Which of the following records will be in the result? Assume each record has the schema (A, B, C, D). (a) (3, 3, 1, 6) (b) (6, 4, 4, 1) (c) (2, 3, 3, 5) (d) (3, 5, 3, 1) 11. Compute R ⋈R.A<S.C S. (this is theta join). Which of the following records will be in the result? Assume each record has the schema (A, B, C, D). (a) (2, 3, 3, 5) (b) (6, 4, 4, 1) (c) (6, 4, 3, 1) (d) (3, 5, 1, 6) 12. Compute R ⋈R.B < S.D AND R.A<S.C S. [this is theta join]. Which of the following records will be in the result? Assume each record has the schema (A, B, C, D). Add description here! (a) (3, 3, 3, 5) (b) (6, 4, 3, 1) (c) (2, 3, 3, 5) (d) (3, 5, 1, 6) 13. Compute π C, D (S). Which of the following records will be in the result? (a) (5, 1) (b) (4, 3) (c) (3, 3) (d) (3, 5) 14.Compute π B, C (R ⋈ S). Which of the following records will be in the result? Add description here! (a) (6, 4) (b) (4, 3) (c) (5, 1) (d) (5, 3) 15.Compute π B (R) - π B (S). Which of the following records will be in the result? (a) (6) (b) (4) (c) (1) (d) (5) 16.Compute π B (R) ∩ π B (S). Which of the following records will be in the result? (a) (6) (b) (1) (c) (2) (d) (5) 17. Compute R ⋈ S. Which of the following records will be in the result? Assume each record has the schema (A, B, C, D) Add description here! (a) (3, 3, 1, 6) (b) (6, 4, 4, 1) (c) (3, 5, 1, 6) (d) (3, 5, 3, 1) 18. Compute π B (R) U π B (S). Which of the following records will be in the result? Add description here! (a) (6) (b) (1) (c) (2) (d) (5) 19.Assume a relation R(A, B) with n unique records, and a relation S(B, C) with m unique records. When you compute the natural join between R and S you shall get r records as the result. Which of the following assumptions are correct in terms of (n, m, r)? Add description here! (a) (5, 4, 25) (b) (2, 3, 8) (c) (3, 3, 10) (d) (2, 3, 6) 20:Which functional dependency types is/are not present in the following dependencies? Empno -> EName, Salary, Deptno, DName DeptNo -> DName EmpNo -> DName a) Full functional dependency b) Partial functional dependency c) Transitive functional dependency d) Both B and C 21.The database design prevents some data from being stored due to _______. a. Deletion anomalies b. Insertion anomalies c. Update anomalies d. Selection anomalies 22.Consider the schema R(S,T,U,V) and the dependencies S→T, T→U, U→V, V→S. Let R= {R1,R2} such that R1∩R2=Φ. Then the decomposition is : a. not in 2NF b. in 2NF but not in 3NF c. in 3NF but not in 2NF d. in both 2NF and 3NF Consider the schema R(S,T,U,V) and the dependencies S→T, T→U, U→V, V→S. Let R= {R1,R2} such that R1∩R2=Φ. Then the decomposition is : a. not in 2NF b. none of the above c. in 3NF but not in 2NF d. in both 2NF and 3NF 24. 5NF is designed to cope with : a. Transitive dependency b. Join dependency c. Multi valued dependency d. None of these 25.Consider a relation R(A, B, C, D) with the following functional dependencies: A -> (B, C, D), (A, D) -> (B, C) and (C, D) -> (A, B). Identify the candidate key(s). a. {A} b. {A}, {C, D} c. {A}, {C, D}, {A, D} d. {C, D} 26. Consider the relation Sale(Date, Customer, Product, Vendor, VendorCity, SalesRep) {Date, Customer, Product} is the composite candidate key and the following functional dependencies are also given: Vendor -> VendorCity, Product -> Vendor What is the highest normal form of the sale relation? a. 0NF b. 1NF c. 2NF d. 3NF 27. R(A,B,C,D) is a relation, Which of the following does not have a lossless join dependency preserving BCNF decomposition a. A->B, B->CD b. A->B, B->C,C->D c. AB->C, C->AD d. A->BCD 29. Which functional dependency types is/are not present in following dependencies? StaffNo, BranchNo -> StaffName, BranchName, Position, DOB StaffNo -> StaffName, Position, DOB BranchNo -> BranchName a. Full functional dependency b. Partial functional dependency c. Transitive functional dependency d. Both B and C 30. Which of the following columns in a table cannot be updated? a. DATE type columns in the table b. Columns which allows NULL values in the table c. A primary key column which also serves as foreign key reference in another table d. All of the above 31.The three language components of a database management system (DBMS) like DDL, DCL, DML. Two different types of people (users and practitioners) are concerned with them. Which of them do users of a DB a. DDL b. DML c. DDL And DCL d. DCL And DML 32. Cuticular transpiration is --------- of total transpiration ? 6-8% 5-7% 7-9% 4-6% 33. ----------- potential is the measure of the change in water potential of a system due to the presence of solute molecules ? Osmotic Pressure Both of these None of these 34. In the root cells ------- pathway becomes discontinuous in the endodermis due to the presence of casparian strip. Tonoplast Apoplast Symplast Vacuolar. 35: In plants, the neighbouring cells are connected with one another by---------- ? Plasmodesmata Cell walls Vacuoles Both ‘A’ & ‘B’ Author: A.J. Bhatti
